Alcuni messaggi e notizie interessanti, provenienti da vari forum e mailing
list.


Saluti,

Fausto Marzoli
8052 Group Moderator

--------------------
ISP1181: Full-speed Universal Serial Bus interface device
http://www.semiconductors.philips.com/pip/ISP1181DGG (UPDATE)

--------------------
NE56604-42: System reset with built-in watchdog timer
http://www.semiconductors.philips.com/pip/NE56604-42D (UPDATE)

NE56610/11/12-XX: System reset
http://www.semiconductors.philips.com/pip/NE56610-25GW (UPDATE)

SA56600-42: System reset for lithium battery backup
http://www.semiconductors.philips.com/pip/SA56600-42D (UPDATE)

SA56606-XX: CMOS system reset
http://www.semiconductors.philips.com/pip/SA56606-20GW (UPDATE)

SA56614-XX: CMOS system reset
http://www.semiconductors.philips.com/pip/SA56614-20GW (UPDATE)

--------------------
little circuit board for servos which can replace the analog ones, it uses
I2C and read tell the servo what position to move to, and how quickly to do
it. It uses I2C to talk to the servos, and also has feedback on how much
force is being exterted on the servo

http://www.colinmackenzie.net/

--------------------
philips 87C591

http://www.semiconductors.philips.com/acrobat/datasheets/P8XC591_2.pd

--------------------
PCF8583
A GOOD include file ( C. )for PCF8583
Needed to set,read the time and alarm ect.

http://www.semiconductors.philips.com/acrobat/applicationnotes/an96119.pdf

--------------------


--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da vari forum e mailing
list.

Saluti,

Fausto Marzoli
8052 Group Moderator


--------------------
Mp3Player

www.myplace.nu/mp3
There you can find sourcecode for a mp3player with a hdd, based on an avr
device.

--------------------
8051 and a small keyboard and LCD

PC keyboard to '51 is found in the input half of
http://www-us.semiconductors.philips.com/acrobat/applicationnotes/AN434.pdf.

--------------------
8051 and a small keyboard and LCD

Go to this site and search for keyboard theory and interfacing in the
PC hardware section. Its a very informative site.
http://www.hut.fi/Misc/Electronics/epanorama/index.html
You will get many ready made codes to interface PC keyboard with 8051

--------------------
Flowchart Generator

The tool you're looking for is VISIO.
It can read 'C' files and convert it into flowcharts.
Pretty good for reverse  engineering

--------------------


--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da vari forum e mailing
list.

Il Triscend E5 che e' citato a proposito del VHDL e' un microcontrollore core
8052 con a bordo come periferica anche una logica programmabile.


Saluti,

Fausto Marzoli
8052 Group Moderator



--------------------
I want to make 8051 programmer myself

http://www.specs.de/~danni/tools/proflash/index.htm
http://www.bonus.com/contour/Robots_making/http@@/www.xs4all.nl/~sbolt/e-ser89.h\
tml

--------------------
I want to make 8051 programmer myself

http://www.batronix.com/electronic/circuits/index.shtml
You can find a sheets in GIF & Eagle formats

--------------------
Triscend E5

Anyone any suggestions for VHDL course on line anywhere ?

www.mentor.com/uk/events/fa_seminar/fa_seminar_invite_enews.cfm

'VHDL Made Easy' by Pellerin, Taylor. ISBN 0-13-650763-8 Prentice Hall,

--------------------


--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.

Saluti,

Fausto Marzoli
8052 Group Moderator

----------
Any way to compress a program...

CodeCompressor51 is a post linker optimisation utility used by Raisonance 51
and XA compilers to dramatically reduce code size.  We have seen improvements
over the final Keil output by a minimum of 7% to a maximum of 35%.  We
advertise 20% as typical.  The Raisonance tools are 100% source and directive
compatible with Keil's C51 so porting over is trivial.  Our linker is more
capable with regards to FLASH, Code Banking, generic pointers and indirect
function calls.
Check out our web pages at either www.amrai.com or www.raisonance.com
depending on where you are located.  There is a complete writeup on CC51 there

----------
Decompile

There are various free disassemblers available which can turn 8052 binary
files back in to assembly code.

Haven't seen anything which attempts to go all the way back to C. This topic
(and some of the difficulties) are discussed at
http://compilers.iecc.com/comparch/article/90-09-070

----------
C508 socket adapter for MQFP package

Emulation Technology
http://www.emulation.com/

Winslow AdaptICs
http://www.winslowadaptics.com/homepage.htm

----------
P87LPC76x signature bytes

signature bytes:

LPC 762 addresses 30h,31h,60h value 15h,DDh,03h
LPC 764 addresses 30h,31h,60h value 15h,DDh,00h
LPC 767 addresses 30h,31h,60h value 15h,DDh,01h
LPC 768 addresses 30h,31h,60h value 15h,DDh,04h
LPC 769 addresses 30h,31h,60h value 15h,DDh,02h

http://www-us.semiconductors.philips.com/acrobat/applicationnotes/AN466_1.pdf

----------
READ mode of PCF8574 I/O expander

Basic information about the device is at:
http://www.semiconductors.philips.com/pip/pcf8574t (that is the surface
mount version). From that page you can download the data sheet in pdf
format.

----------
Loooking for AT89C52 assembler

You can get a free universal cross-assembler which runs both on Windows and
Unix on
http://www.alfsembler.de/


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8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.

Saluti,

Fausto Marzoli
8052 Group Moderator


----------
How to connect 8052 to server via modem
An example of such a device can be found at
http://members.aol.com/cpu8052

----------
Keil C Expanding Memory

This very issue has recently been discussed on the Keil site:
http://www.keil.com/discuss

The latest version provides 'far' pointers for this purpose.

C51: IMPLEMENTING XDATA BANKING
http://www.keil.com/support/docs/1185.htm


--
Fausto Marzoli
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Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.

Saluti,

Fausto Marzoli
8052 Group Moderator

----------
2 UART microcontroller
There are some of them from Siemens (now Infeneon): 80C537, 80C517 and so on.
http://www.infineon.com/cgi/ecrm.dll/ecrm/scripts/prod_ov.jsp?oid=13739&cat_oid=\
-8136

----------
There is a safe way to digitally select between two free running clocks, have
a look at

http://www.xilinx.com/xcell/xl24/xl24_20.pdf

This circuit is used in many applications where the CPU has to be throttled
to save power. Clock A could be direct driven from the oscillator and Clock B
from a programmable divider

----------
assembler for Atmel at89s8252

Keil demo download at:
http://www.keil.com/demo/default.htm

There's also a link to request a free CD
http://www.keil.com/demo/cdrom.htm

----------
how I can expand the 8051 based system RAM to more than 64 KB?

To expand beyond 64Kb with a normal 8051 variant then you have to resort to
paging, using one or more I/O lines as additional address lines to the ram
address decoder, so that you can have n x 64k pages, you need to keep a track
of which bank you are using with your software.
Some C compilers (IAR for example) support paging of memory.
Keil have recently "improved & extended" (they say) their banking support.


--
Fausto Marzoli
8052 Group Moderator

Sto cercando (senza successo) il codice sorgente dell'application note:
"AN465 Using the 87LPC76X in multi-master I2C applications"

L'AN infatti e' un file PDF, ed estrarne la parte di codice sorgente non e'
agevole.

Qualcuno lo ha trovato, o ha gia' provato ad utilizzare il codice di questa
AN?

Grazie.


--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.

Saluti,

Fausto Marzoli
8052 Group Moderator

----------
Philips Semiconductors launches next-generation series of rotational speed
sensors targeted at the automotive industry with much higher air gap
http://eNews.Semiconductors.com/news/content/file_716.html

----------
Philips Semiconductors launches first family of maintenance and control ICs
for communications infrastructure equipment
http://eNews.Semiconductors.com/news/content/file_717.html

----------
TDA8020HL: Dual smart card interface
http://www.semiconductors.philips.com/pip/TDA8020HL

----------
about M5450
the datasheet of component? The under url takes to ST
site about this component
http://www.st.com/stonline/books/pdf/docs/1136.pdf

----------
Floating Point Chips Wanted..
Have a look at:
http://www.al-williams.com/awce/pak1.htm

----------
running Basic-52 on ds80c320
Ver 1.3 of the interpreter is available from Elektor for approx £11.00.
Site:www.elektor-electronics.co.uk .This was published in the Feb 2001 issue.
This can be used with high speed micros.

----------
AT command to 8051
You can find some of commands at
http://www.citilink.com/~kae/clink_faq/connecting/general/hayes.html

----------
assembler for Atmel at89s8252
ftp://www.atmel.com/pub/atmel/asmb51.exe
ftp://www.atmel.com/pub/atmel/mlasm51.exe

----------
assembler for Atmel at89s8252
you might also want to try
http://www.vaultbbs.com/pinnacle"
Pinnacle 52
which now supports the Atmel 89S8252 internally, and simulates it, too.

----------
89C51/89C2051 programming

http://chaokhun.kmitl.ac.th/~kswichit/

----------
Code for SPI with 8051

http://www.atmel.com/atmel/acrobat/doc0898.pdf and
ftp://www.atmel.com/pub/atmel/isp_app.zip

----------
89C51/89C2051 programming

http://www.specs.de/~danni/tools/proflash/index.htm


--
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8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.

- Source per datasheet: http://www.datasheetlocator.com/


Saluti,

Fausto Marzoli
8052 Group Moderator


----------
Resources on USB
http://www.lvr.com/usb.htm, Jan Axelson's page and the author of the book
"USB Complete"

----------
s-record file format?
http://www.bigfoot.com/~sanmail

---------------------------------------------------------
s-record file format

Motorola's Application Snapshot AS80, "UNDERSTANDING S-RECORDS AND PROBLEMS
WITH DOWNLOADING" by Charles Melear.

http://www.dimensional.com/~rkaiser/rek/mot%20s-rec.html

----------
Designing lcd menu with C
use the switch() statement. An example can you found at:
http://www.specs.de/~danni/appl/soft/c51/thclock/index.htm

----------
Keil 'C': on function pointers & overlaying
App Note APNT_129;
Knowledgebase http://www.keil.com/support/docs/210.htm

----------
80C51_FAM documents at
http://www-us.semiconductors.philips.com/handbook/various_66.html

----------

--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.


Saluti,

Fausto Marzoli
8052 Group Moderator


----------
Dallas 89c420 Low Cost Programmer
http://pdfserv.maxim-ic.com/arpdf/Design/89c420_userguide.pdf

----------
2 UART microcontroller

Do you have SPI ?
Check for MAX3100 ... from Maxim..
As many RS232 / IrDA as you can handle on 1 SPI bus.
Easy to use !
request online samples !  (2 pieces)

----------
Somebody alread used the can bus 80c930
http://www.systronix.com/uCAN2/ucan2_examples.htm

----------
89C51/89C2051 programming
http://chaokhun.kmitl.ac.th/~kswichit/

----------

--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.


Saluti,

Fausto Marzoli
8052 Group Moderator

----------
the path to the "general" IIC appnotes is somewhat obscure, but
here it is:  http://www-us.semiconductors.philips.com/i2c/support/#appnotes

----------
http://www-us.semiconductors.philips.com/acrobat/various/I2C_BUS_SPECIFICATION_3\
.pdf

----------
AT89S8252 InSystemProgrammer for Linux ?
http://www.ai.mit.edu/~vona/bass/bass-details-billy.html
Look for "Programming the 8252"

----------
Development software for linux
Is there any <b>8051 asemmblers, simulators and C compilers</b> in Linux
environment?
of course there is: try
http://sdcc.sourceforge.net
the sdcc (small device c compiler) is quiet flexible and makes a pretty good
code.

----------
4x20 lcd
Take a peek at these 'C' routines. These were written for two displays
shareing data lines, and work like a charm. They only support writing not
reading.
http://home.earthlink.net/~martine001/lcd.c

----------




--
Fausto Marzoli
8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.


Saluti,


Fausto Marzoli
8052 Group Moderator



---------------------------------------------------------
Message Subject: AT89S8252 InSystemProgrammer for Linux ?
Posted By:       Andreas Krause (mailto:a.krause@...)
Date/Time:       06-07-01 00:54
Message Link:    http://www.8052.com/forum/read.phtml?id=12270

Hi !
I used to download code "in system" via par-port with a small
windows tool by aec-electronics.
But now I'm getting rid of windows and im searching for a linux tool, that
does the same:
input: hex or bin file
output: via a "few wire connection" from lpt to the controller.

does anyone know about such a program or even knows where to seach ?
thanks a lot !
greetings
andreas


---------------------------------------------------------
Message Subject: RE: AT89S8252 InSystemProgrammer for Lin
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       06-07-01 11:59
Message Link:    http://www.8052.com/forum/read.phtml?id=12283

If you get really stuck, use VMware ? I expect it will give you direct port
access.

Steve


---------------------------------------------------------
Message Subject: RE: problem with 4x20 lcd.
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       06-07-01 16:22
Message Link:    http://www.8052.com/forum/read.phtml?id=12289

try this
http://www.epemag.wimborne.co.uk/resources.htm

download lcd1.pdf and lcd2.pdf

about the middle of the page


--
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8052 Group Moderator

Alcuni messaggi e notizie interessanti, provenienti da varie mailing list.

Development kit per USB:
http://www.dlpdesign.com/usb/
Produttore:
http://www.ftdichip.com/


Per chi usa l'emulatore PDS51:
-------------------------------------------------------------
Hello all PDS51 users,
We have posted a new version of the PDS51W IDE on our web site
(www.pds51.com).

This version resolves support for the PDB66x-Rx2 board MOVX internal
only/mixed operation. There are also a few minor bug fixes and enhancements.

For a full list of changes from your version to 3.36 please refer to the
CHANGES.TXT file.

Please feel free to update your copy.

best regards,
The PDS51 support team
-------------------------------------------------------------



Saluti,


Fausto Marzoli
8052 Group Moderator




---------------------------------------------------------
Message Subject: RE: Two telephones on a line
Posted By:       Gil Simon (mailto:gil_simon_2k@...)
Date/Time:       06-06-01 05:32
Message Link:    http://www.8052.com/forum/read.phtml?id=12241

Hi Oleg,

Buy a domestic telephone exchange. A 1 to 2 line, one public line and two
  extensions connected to it.

You can ring eachother, ring out side and get ring selectively to both from
  outside.

Or, if want to do it yourself then focus on making such an exchange rather
  than asking otherwise.

Surf mitel.com for the necessary application notes and DTMF encoders and
  decoders. Use them all with the micro.

Be wise not to program the micro to generate DTMF, that you can do in 30
  minutes and less than 2 $.

Have fun

Simon


---------------------------------------------------------
Message Subject: RE: Reading an Output Port
Posted By:       erik malund (mailto:malund@...)
Date/Time:       06-06-01 06:46
Message Link:    http://www.8052.com/forum/read.phtml?id=12247

   1) John: "The 82C55 is not bit addressable", last I looked it
  was.  What do you mean? 2) Mohit: The method described by Henk is the
  "standard way" I use it, only in cases where you are at a program
  crash or some such would I attempt to read the actual port latch status.
  This can be done by the method described in
http://www-us.semiconductors.philips.com/acrobat/various/80C51_FAM_HARDWARE_1.pd\
f
on page 5.

Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: question about a keyboard
Posted By:       erik malund (mailto:malund@...)
Date/Time:       06-06-01 06:58
Message Link:    http://www.8052.com/forum/read.phtml?id=12250

   While this is not an answer to your question (why do you use the archaic
  stuff) you should be able to extract whet you need from
http://www-us.semiconductors.philips.com/acrobat/applicationnotes/AN434.pdf


Have fun,

Erik




--
Fausto Marzoli
8052 Group Moderator

Da oggi e' presente sul sito http://www.8052.it una pagina con elencati i
titoli di alcuni libri interessanti per gli sviluppatori.

Se voleste includere in questa lista dei titoli, e' sufficiente comunicarmelo
con un messaggio.

Ricordo che qualunque suggerimento, commento o idea per altre pagine sara'
benvenuto.

Saluti,


--
Fausto Marzoli
8052 Group Moderator

Risposta a rinux (15:32, martedì 05 giugno 2001):

> utilizzo linux abbondandemente

Per chi usa Linux come me, e' possibile anche usare cross-assembler e
cross-compiler per 8052 sotto linux, in particolar modo quelli che girano
originalmente sotto DOS.

Io lavoro in questo modo. Ho descritto come fare alla pagina
http://www.precma.com/tooltips/crosslinux.htm

Sto provando anche ad usare la nuova IDE Keil sotto Linux, usando l'emulatore
wine. Se avro' buoni risulati lo comunichero', per ora non funziona
perfettamente...

Saluti,


--
Fausto Marzoli
8052 Group Moderator

Inoltro una selezione delle parti che mi sembrano piu' interessanti dei
messaggi del forum 8052.


Saluti,

--
Fausto Marzoli
8052 Group Moderator

---------------------------------------------------------
Message Subject: I2C interface for 24C16 + DS1307
Posted By:       Magnus Alfredsson (mailto:epkma@...)
Date/Time:       06-05-01 00:59
Message Link:    http://www.8052.com/forum/read.phtml?id=12191

I'm working on a project at home where I have a 8031 that I setup so the P1.6
  and P1.7 is connected to an I2C bus. On this bus I have one 24C16 and one
  DS1307.

I had some code that makes it possible to read and write from the 24C16. But
  when I started to use this for the DS1307 I had to add some 'wait' between
  etch step otherwise the data didn't com out.

Now the the real problem! Now and then, the DS1307 flips out and does not
  response when I try to read it!? I just get FF back.

The code I'm using is not handling the ACK in an nice way.

Is there anyone out there that has an nice and work code block for accessing
  an I2C bus? (If so please mail me...)

I've searched the net but haven't been able to find and god code...

BTW the project is about an automatic flower watering system, with RS232
  command interface and an LCD-display.

/Magnus


---------------------------------------------------------
Message Subject: RE: I2C interface for 24C16 + DS1307
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       06-05-01 02:36
Message Link:    http://www.8052.com/forum/read.phtml?id=12193


http://www.specs.de/~danni/appl/hard/i2c/index.htm



---------------------------------------------------------
Message Subject: RE: I2C interface for 24C16 + DS1307
Posted By:       Charles Bannister (mailto:cbanni3061@...)
Date/Time:       06-05-01 04:48
Message Link:    http://www.8052.com/forum/read.phtml?id=12197

Hello Mr. Magnus Alfredsson,

Trying looking at the following:

www.atmel.com/pub/atmel/aat24cxx.exe for
Interfacing AT24CXX Serial EEPROMs with 8051's type ic's.

and

www.atmel.com/pub/atmel/aaat25cxx.exe for Interfacing AT25CXX Serial EEPROMs
  with 8051's type ic's.

Thank you,

Charles Bannister

utilizzo linux abbondandemente
:)


----- Original Message -----
From: Fau Marz <faumarz@...>
To: 8052 Mailing List <8052@yahoogroups.com>
Sent: Tuesday, June 05, 2001 10:45 AM
Subject: [8052] Linux


> Una curiosita': qualcuno tra i membri della lista utilizza il sistema
> operativo Linux?
>
> Qualcuno e' comunque interessato a Linux?
>
>
> Saluti,
>
> --
> Fausto Marzoli
> 8052 Group Moderator
>
>
> --
> Home Page della mailing list 8052: http://www.8052.it/
>
> Per cancellare l'iscrizione a questa Mailing List, manda un messaggio
all'indirizzo:
> To unsubscribe from this group, send an email to:
> 8052-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>

Una curiosita': qualcuno tra i membri della lista utilizza il sistema
operativo Linux?

Qualcuno e' comunque interessato a Linux?


Saluti,

--
Fausto Marzoli
8052 Group Moderator

Inoltro una selezione delle parti che mi sembrano piu' interessanti dei
messaggi del forum 8052.


Saluti,

--
Fausto Marzoli
8052 Group Moderator

---------------------------------------------------------
Message Subject: RE: Small LCD
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       06-04-01 03:37
Message Link:    http://www.8052.com/forum/read.phtml?id=12169

Hi!
Do you know Elatec? They are selling:
EL 0801A/B/C (1x8)
EL 0802A/B/C (2x8)
EL 1201A/B/C (1x12)
Good luck!


---------------------------------------------------------
Message Subject: RE: Keil Compiler Hex Output
Posted By:       Dincer Aydin (mailto:)
Date/Time:       06-04-01 16:05
Message Link:    http://www.8052.com/forum/read.phtml?id=12185

http://chaokhun.kmitl.ac.th/~kswichit/
has a program to sort such a hex file.
Delphi source code is available.

Regards,

Dincer Aydin
www.geocities.com/dinceraydin/



--
Fausto Marzoli
8052 Group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.



Saluti,

--
Fausto Marzoli
8052 group Moderator

---------------------------------------------------------
Message Subject: RE: Phase angle, Duty Cycle
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       06-03-01 03:44
Message Link:    http://www.8052.com/forum/read.phtml?id=12145

I would suggest to make a loop with the use of memory in which the bit on
  P1.0 is shifted say 360 times (degrees) and comes out again having the same
  value but 180 times later. Create a 360 bit shift register. This way it
  doesn't matter what the value of P1.0 is, P1.1 will always have the same
  duty cycle. I couldn't tell you how to do that though because I am not a
  good programmer. But here is what I mean.

bit1..............bit180..........bit360
^read from P1.0___^write for P1.1
and start reading the values for P1.1 from bit180


---------------------------------------------------------
Message Subject: RE: Phase angle, Duty Cycle
Posted By:       Henk van den Broek (mailto:h_v@...)
Date/Time:       06-03-01 06:34
Message Link:    http://www.8052.com/forum/read.phtml?id=12148

What Aad said is true, but you HAVE to meet two conditions:

1) Only the DUTYcycle of the inputsignal may vary, NOT the FREQUENCY.

2) You MUST have a clocksignal for the shiftregister which is absolutely
  synchron with the input signal, but exact 360 times the input frequency. So
  this clocksignal must be derived from the circuit that delivers the input
  signal for your microcontroller. Simplest way is NOT to connect your
  inputsignal to P0.0, but to an interrupt inputpin. Make the pin negative
  edge detect, and HIGH preority interrupt. So you can measure the period
  time. (Time between two input interrupts). Devide this time by 360 and y
  u'll have the nessesary sampleclockfrequency. Use a timer to generate 360
  (low preority) interrupts per inputcycle.

Make a buffer in RAM of 360 continuous bits.
Also make a software counter for clockpulses
Now, after having used one inputcycle to define the sampleclockfrequency, you
  have to do the following:

when an external interrupt occurs (inputsignal becomes low)
* reset the sampleclockcounter
* Reset the softwareclockpulscounter
* write the momentary value of the inputpin to bufferlocation 0


when an timerinterrupt occurs:
* Increment the softwareclockpulcounter by one
* Write a sample of the signalinputpin to the RAMbufferlocation defined by
  the softwareclockpulscounter.

If you have reached RAMbufferlocation 359, the next location should be
  location 0, because 360 degrees and 0 degrees are the same position (start
  of cycle).

In your MAIN program, you have to set a value between 0 and 359 in a
  variable, wich stands for the phaseshift. If you compare this value in your
  timer-interruptroutine with the softwareclockpulscounter and it is equal,
  you know you have to start writing the value from bufferlocation 0 (zero) to
  P0.1, the next interrupt bufferlocation 1 to P0.1, etc. So your inputpin
  writes your buffer, the outputpin P0.1 reads the buffer, with an adjustable
  shift between them of 0 to 359 degrees.

Hope this helps you...
Henk


---------------------------------------------------------
Message Subject: RE: 8052.COM USER HOME PAGES
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       06-03-01 14:11
Message Link:    http://www.8052.com/forum/read.phtml?id=12156

Just getting <b><i>anything</i></b> up there was a bit of a challenge - but
  many thanks to Craig who's been working hard on it.

Not sure exactly what I am going to put there, as the rules say I mustn't
  advertise...  ;-)

A.


---------------------------------------------------------
Message Subject: RE: communication using 75176
Posted By:       Shankara (mailto:shankroo@...)
Date/Time:       06-03-01 07:09
Message Link:    http://www.8052.com/forum/read.phtml?id=12150

While I have been able to solve most of the communication problems
  occassioanally a byte which is cont consistent seems to be read.Is there no
  way of vetting this except through a CRC check.The inor I am transmitting is
  only two bytes long I think a CRC is an over kill ANY other way???


---------------------------------------------------------
Message Subject: RE: Send data 16 bit via RS232
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       06-03-01 14:22
Message Link:    http://www.8052.com/forum/read.phtml?id=12157

See the Thread, <i>"Keil C: read two byte?"</i> for a discussion of
  addressing the 2 bytes of an int (the discussion is not specific to Keil).

<b>Beware:</b> When sending binary data on an RS232 link, you must be sure
  that <b><i>nothing</i></b> on the link (hardware or software) will try to
  interpret any of your data as any sort of control condes (<i>eg</i>,
  0x0D=CR; 0x0A=LF; 0x11=XON; 0x13=XOFF), and that everything on the link can
  correctly handle 8-bit data.


---------------------------------------------------------
Message Subject: RE: Keil C : read two byte?
Posted By:       Thomas Zepf (mailto:thzepf@...)
Date/Time:       06-03-01 04:07
Message Link:    http://www.8052.com/forum/read.phtml?id=12146

Here a example how I am doing the things:

#define LowB(x) (*((UINT8*)&amp;(##x)+1))
#define HighB(x) (*((UINT8*)&amp;(##x)+0))

access is then done:
LowB(wordvar)=P0;
HighB(wordvar)=P1;

Thomas



---------------------------------------------------------
Message Subject: RE: Keil C : read two byte?
Posted By:       Bryan Whitton (mailto:bryanw@...)
Date/Time:       06-03-01 13:13
Message Link:    http://www.8052.com/forum/read.phtml?id=12153

I think that this is what you may be looking for.  The generated assembly is
  simply the same as your assembly code.  At least in the Raisonance compiler.
  I assumed that you would want to access the variable as an integer otherwise
  the union could be removed. /*
	 This simple routine assumes that you will be loading a variable wordvar with
  the two bytes from P0 and P1 and then accessing wordvar as an int.
	 The first step creates a structure consisting of two unsigned chars.
	 The second step creates a union of these two unsigned chars an a single
  unsigned int. The code simply loads each byte with P0 or P1 to read the
  values simply read wordvar.x. */
#include &lt;reg52.h&gt;
#include &lt;stdio.h&gt;

struct Dual_Chars
{
unsigned char Hi_X;
unsigned char Lo_X;
};

union dual_access
{
	 unsigned int x;
	 struct Dual_Chars Test;
} wordvar;

void main (void)
{
while (1)
	 {
	 wordvar.Test.Lo_X = P0;
	 wordvar.Test.Hi_X = P1;
	 printf (&quot;This is the contents of P0 and P1 %x.\n&quot;,wordvar.x);
	 }
}

maziar navahan wrote:
-------------------------------
i require read two byte from P0,P1 and
write in one &amp;quot;int var&amp;quot; in C
in assembelly is very simple
   mov Lowbyte,P0
   mov HighByte,P1
in C how do it without get most time
note no use #programa Asm Directive !
i am require only &amp;quot;c&amp;quot; code

thank for help




---------------------------------------------------------
Message Subject: RE: Keil C : read two byte?
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       06-03-01 14:05
Message Link:    http://www.8052.com/forum/read.phtml?id=12155

Craig's approach - using shifts - will <b>always</b> work on <b>any</b>
  compiler and <b>any</b> target with <b>any</b> byte ordering.

Bryan's approach - using a union - might be quicker, but requires you to
  <b>know</b> the Compiler's byte ordering; it may not be portable to a
  different compiler or different processor.

Thomas' approach looks like trying to emulate the action of a union; it'd be
  simpler (probably also more efficient) to just use a union!


---------------------------------------------------------
Message Subject: RE: Keil C : read two byte?
Posted By:       maziar navahan (mailto:mnavahan @yahoo.com)
Date/Time:       06-03-01 21:52
Message Link:    http://www.8052.com/forum/read.phtml?id=12161

maziar navahan
for Craig Steiner
try it but no!
the compiler is very bad because generate this code! (compiler out src)

; int  inint (void) {

	 RSEG  ?PR?inint?SERIAL_1
inint:
	 USING 0
			 ; SOURCE LINE # 58
;  return( ( P0 &lt;&lt; 8) + P1);
			 ; SOURCE LINE # 59
	 MOV   R7,P0
	 MOV   A,R7
	 MOV   R6,A
	 MOV   R5,P1
	 MOV   R4,#00H
	 CLR   A
	 ADD   A,R5
	 MOV   R7,A
	 MOV   A,R4
	 ADDC  A,R6
	 MOV   R6,A
; }
			 ; SOURCE LINE # 60
?C0010:
	 RET


---------------------------------------------------------
Message Subject: RE: Keil C : read two byte?
Posted By:       maziar navahan (mailto:mnavahan @yahoo.com)
Date/Time:       06-03-01 21:57
Message Link:    http://www.8052.com/forum/read.phtml?id=12162

for Thomas Zepf
please more comment for me for
#define LowB(x) (*((UINT8*)&amp;(##x)+1))
how do it?


---------------------------------------------------------
Message Subject: Starting Project w/N scale trains
Posted By:       Christopher Cicle (mailto:ccicle@...)
Date/Time:       06-03-01 01:33
Message Link:    http://www.8052.com/forum/read.phtml?id=12144

Hey everyone,
Sorry if this sounds stupid or ignorant, but I'm new to the electronics field
  and Microcontroller field in general. My friend told me about this site and
  so here I am. My question is I'm trying to design a system that will let me
  control model trains, using the 8052, but am not up to speed on a particular
  device to use for the current need to start the little buggers. I was
  thinking about Mosfets but don't know enough about them to even venture a
  guess. I would be very thankful if you all knew of a devic I can research
  that is cheap and well available that I can use for this project. Any help
  will be greatly appeciated. Thank You in advance.


---------------------------------------------------------
Message Subject: RE: Starting Project w/N scale trains
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       06-03-01 06:06
Message Link:    http://www.8052.com/forum/read.phtml?id=12147

Hi! I have built some models. I think, I can help you, but I am sorry, I am
  not so perfect in English, I can't understand what do you really need. Are
  you looking for evaluating board (some of kits) to make the controller? What
  do you want to control? Only one engine or whole model? Do you need to
  change the motor power or only switch it on and off? Are you able to build
  your own device (make layout, mount components, write a program for micro)
  or are you looking for ready one? You can write direct to my email, I will
  try to help you.

PS
If I have understood you well, you should to take a look at VMOS transistors,
  not MOSFET. * * * * *
There is no stupid question. Only answer can be stupid. If you don't make
  mistakes, you probably never learn.


---------------------------------------------------------
Message Subject: RE: Starting Project w/N scale trains
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       06-03-01 13:54
Message Link:    http://www.8052.com/forum/read.phtml?id=12154

Time for a visit to your favourite internet search engine, methinks.

I'm sure there are several sites out there with model control electronics -
  or check out some magazines. BTW: the scale of your model makes very little
  difference to the electronics - so don't limit your searching to 'N' gauge!

For a novice, probably the best way to start is with a kit or a magazine
  project; you can see it working, get to understand it, and then start making
  some changes. You will soon amass enough experience to start your own
  project!


---------------------------------------------------------
Message Subject: Interrupt service routine
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       06-03-01 06:44
Message Link:    http://www.8052.com/forum/read.phtml?id=12149

Hello everybody!
I have a question about interrupt routine. I have been using two interrupts
  in my program, external int.1 & 2. Inputs are conected to the same signal
  int1-direct,int0-via inverter. So, at the beginning of the program I set:

;timer 0 is in timer mode,software controll
MAIN:
CLR   after_ex0
CLR   after_ex1
SETB  EX1  ;external int.1 enable
CLR   EX0  ;external int.0 disable
SET   EA   ;global interrupt enable
JNB   after_ex1,$ ;wait for int.1 service routine end
JNB   after_ex0,$ ;wait for int.0 service routine end
CALL  display_results

and my program is waiting for 1 to 0 transistion on INT1. Interrupt 1 service
  routine is setting only four bits (so as int.0):

IRQEX1:
SETB  TR0   ;starts timer 0
CLR   EX1   ;int.1 disable
SET   EX0   ;int.0 enable
SET   after_ex1
RETI

IRQEX0:
CLR   TR0   ;stops timer 0
CLR   EX0   ;int.0 disable
SET   after_ex0
RETI

My questions is: can I clear EX1 bit during interrupt service routine?
Program should measure the low pulse using timer 0. The results of measuring
  are so amazing - I calculate the input pulse and its duration would be about
  380 machine cycles, but the results of measuring is... 12. I have made
  changes and now, my program looks like below:

MAIN:
CLR   after_ex0
CLR   after_ex1
SETB  EX1  ;int.1 enable
CLR   EX0  ;int.0 disable
SET   EA
JNB   after_ex1,$
CLR   EX1  ;int.1 disable
SETB  EX0  ;int.0 enable
JNB   after_ex0,$
CLR   EX0  ;int.0 disable
CALL  display_results


IRQEX1:
SETB  TR0   ;starts timer 0
SET   after_ex1
RETI

IRQEX0:
CLR   TR0   ;stops timer 0
SET   after_ex0
RETI

And the results are diffrent (about 30 times!!!). Why?
I can evaluate the problem myself, but at this moment I haven\\\'t my ICE.
  Could anybody answer my question?


---------------------------------------------------------
Message Subject: RE: Interrupt service routine
Posted By:       Henk van den Broek (mailto:h_v@...)
Date/Time:       06-03-01 09:00
Message Link:    http://www.8052.com/forum/read.phtml?id=12151

Hello Jacek,

first thing I ask myself looking at your code is: do you reset the
  hardwaretimer before starting it? I don't find it back in your program. If
  you stop the counter and restart it without resetting, it will count from
  were it was stopped....so your results are worthless.

So you can extend your code like this to be sure the timer starts at zero:

IRQEX1:
CLR TH0
CLR TL0
SETB TR0 ;starts timer 0
SET after_ex1
RETI

Although it is better to clear the timer just after using its countvalue by
  the displayroutine, so you don't lose time in the interruptroutine and your
  measuring will be more accurate.

A second possebility: your pulseduration is to long for the resolution of the
  counter by your specific crystal fryquency, so the timer overflows....
  Solution: use other Crystal frequency.


You asked:
can I clear EX1 bit during interrupt service routine?

Yes you can, and it is often done.

Henk



---------------------------------------------------------
Message Subject: RE: Interrupt service routine
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       06-03-01 15:41
Message Link:    http://www.8052.com/forum/read.phtml?id=12158

Hello Henk, thank you for you attention.
Yes, I clear the timer before the interrupt routine. I forget this in my
  example. Pulse period I want to measure is about 512us. I have been using
  the crystal 11,0592MHz, so I have machine cycle period 1,085us. The result
  should be near 472 (+/-24 depending on input signal frequency). Timer is in
  16-bit timer mode, so the result should fit into registers. I measured the
  input signal by osciloscope and the period was 512us. I have no idea... Do
  you remember The Muppet Show? The situation is like "Pigs in space!!!" ;-))


---------------------------------------------------------
Message Subject: Small LCD
Posted By:       Donatas (mailto:eziukas@...)
Date/Time:       06-03-01 11:02
Message Link:    http://www.8052.com/forum/read.phtml?id=12152

I need small&cheap LCD dispaling ~6 symbols. I can find only 16x1 or 16x2.
  Maybe somebody have allready found anything like that?


---------------------------------------------------------
Message Subject: RE: Small LCD
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       06-03-01 16:07
Message Link:    http://www.8052.com/forum/read.phtml?id=12159

Hi!
I have an offer for:
1. JH-409 (1x12)
2. JH-676 (2x8)
Made by Shenzhen Jinghua Display Co. in China, but I have heard, that
  internet access in China is censored, so you have to look at your local
  distributors. I have also 1x8 display sample from PICVUE, so you have to
  take a look. Ask your distributor. You are from Lithuania, isn't it? Do you
  know ELTRON? They have a lot of LCD diplays in its offer.

PS
If Chineese are making the display, you can find a lot of offers, because
  there are a lot of people! Forget it, it is a joke. ;-)


---------------------------------------------------------
Message Subject: Keil Compiler Hex Output
Posted By:       Andy Yeong (mailto:andy@...)
Date/Time:       06-03-01 18:57
Message Link:    http://www.8052.com/forum/read.phtml?id=12160

Hi friends,

I realized that the output of compiler (HEX file), the address is in a random
  manner rather than &quot;ascending&quot; order.

For example, the hex output (using metalink assembler) will goes something
like this :
:03 0000 00 12 34 56 78
:10 0003 00 12 34 56 78 90 AA BB and etc
:10 0013 00 and other data

However for keil, the hex output hex is in a random manner whereby address
  and range from anywhere.

Is there some settings that I have missed inorder to achieve an ascending
  output.

This pose a problem for my &quot;homebrew&quot; AT89XX programmer. If the
  next address of data to burn into the flash is lesser than the present
  address, I have to reset the whole process to get back to eariler address.

Thanks !

Best Regards
Andy

-------------------------------------------------------

--
Fausto Marzoli
8052 Group Moderator

Devo fare delle prove su bus I2C, ed avrei bisogno di un sistema per fare i
primi test, come per esempio un convertitore RS-232 <-> I2C con software
relativo da installare su un computer, in modo da poter mandare e ricevere
messaggi sul bus I2C da un PC.

Nessuno sa se esista qualcosa del genere gia' in commercio, o se per esempio
ci siano delle application notes che parlino di questo argomento?

Grazie!

--
Fausto Marzoli
8052 Group Moderator

E' nato il sito 8052.it!!!

All'indirizzo http://www.8052.it troverete la prima bozza di home page.

Il webmaster sono io (Fausto Marzoli), e come prima cosa il sito sara' la
home page della mailing list. Ma in seguito potra' diventare molto di piu'.

Siete tutti invitati a proporre idee, richieste, qualsiasi cosa vi venga in
mente che vi piacerebbe fosse trattata su questo sito. Qualsiasi proposta
verra' presa in considerazione!

Se qualcuno di voi volesse poi collaborare (con articoli, codice, esempi, o
altro) non ha che da contattarmi direttamente all'indirizzo:


faumarz@...

Saluti

--
Fausto Marzoli
8052 Group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.



Saluti,

--
Fausto Marzoli
8052 group Moderator


---------------------------------------------------------
Message Subject: RE: 8051-modem inetrface
Posted By:       tong_tang@... (mailto:)
Date/Time:       05-31-01 15:47
Message Link:    http://www.8052.com/forum/read.phtml?id=12082

i speak english little.
i can connect external modem to 8051

first you must read at command

       exsample
       atdt 3232222     atdt is construction
  control modem call number 3232222

second you must read registor s0-s7
            to set recive auto
thrid   you must simulate cts rts and you  can send data to serial port


this all example

this pc you use hyperterminal of windows98

and connect to com at modem connected
and type this

atdt2332232

and press enter
after you press enter you know.


i teach 8051 with c of keil6.10
and i employee to make hardware

http://go.to/c51



---------------------------------------------------------
Message Subject: RE: serial programming
Posted By:       charles adetiloye (mailto:charlesadetiloye@...)
Date/Time:       05-31-01 11:57
Message Link:    http://www.8052.com/forum/read.phtml?id=12078

Please how do i use my c++ codes to contol the serial port output that would
  be directed to an external IC controlling a servo-mechanism


---------------------------------------------------------
Message Subject: RE: which development tool to buy???
Posted By:       Bert Sesam (mailto:Sesam_Bert@...)
Date/Time:       05-31-01 02:05
Message Link:    http://www.8052.com/forum/read.phtml?id=12063

Tasking is doing all the things i need ...

All libs included ...


not cheap for one-piece designers !!


---------------------------------------------------------
Message Subject: RE: which development tool to buy???
Posted By:       Shelley Potter (mailto:shelleyp@...)
Date/Time:       05-31-01 16:18
Message Link:    http://www.8052.com/forum/read.phtml?id=12086

Check out Raisonance!  They offer various packages that include everything
  you mentioned at a great cost.  Also, they have recently released
  CodeCompressor which can reduce code size by as much as 20%!


---------------------------------------------------------
Message Subject: RE: which development tool to buy???
Posted By:       Shelley Potter (mailto:shelleyp@...)
Date/Time:       05-31-01 16:33
Message Link:    http://www.8052.com/forum/read.phtml?id=12089

Hi Andy, Raisonance also offers free evaluations and CD's.  Also, they offer
  ICE's in a discounted package with the C Compiler etc. They also offer alot
  of different development boards!


---------------------------------------------------------
Message Subject: RE: 8051 C Compiler Design
Posted By:       tong_tang@... (mailto:)
Date/Time:       05-31-01 15:55
Message Link:    http://www.8052.com/forum/read.phtml?id=12084

i teach and traning with c of keil 6.10
and reserch with 8051 connect all hardware to every where in the world.

http://go.to/c51 sorry this web for thailanguage only



---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       ridwan efandi (mailto:ridvvan@...)
Date/Time:       05-31-01 08:53
Message Link:    http://www.8052.com/forum/read.phtml?id=12072

Mr Malund, I think your advise will solve my problem, but to be honest I
  still confused with your explainations (my english is not very well :) )

You tell me to do these (according to me) :
1. change the program, the input is valid is only it is the same for at least
  100ms 2. connect a 100 ohm resistor fronn +5 to the input pin
3. connect a capacitor 1uf  from the input pin to the ground
4. put the switch between the input pin and ground
5. connect a tantalum capacitor (100uf)
from the +5 which is located near the 100 ohm resistor to the ground

could you please tell me more detail??
I'm realy realy sure that there are still many mistake in my interpretation.
(hope there is a schematic diagram that makes all the things clear)


thanks for all the help (especially for Mr Malund and Mr Sieraad)


best regard,


ridwan efendi


---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-31-01 12:21
Message Link:    http://www.8052.com/forum/read.phtml?id=12079

"1. change the program, the input is valid is only it is the same for at
  least 100ms" This will keep you from picking up short noise pulses on
  the line.

"2. connect a 100 ohm resistor fronn +5 to the input pin"
   Reduce the impedance of your control line to reduce the noise voltage
  generated by noise engergy coupled to your control line. "3. connect a
  capacitor 1uf from the input pin to the ground" Noise suppression again
"4. put the switch between the input pin and ground"
   Standard switch connection for the '51
"5. connect a tantalum capacitor (100uf)
from the +5 which is located near the 100 ohm resistor to the ground"
   Absorb the noise enregy discharged through the 100 ohms.

Hope this helps

Erik




---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       ridwan efandi (mailto:ridvvan@...)
Date/Time:       05-31-01 21:19
Message Link:    http://www.8052.com/forum/read.phtml?id=12090

I can't wait to make these changes, thanks for the detail.
I'll tell you the result...


best regard,

ridwan


---------------------------------------------------------
Message Subject: Thanks everyone
Posted By:       Lee (mailto:)
Date/Time:       05-31-01 22:55
Message Link:    http://www.8052.com/forum/read.phtml?id=12092

Thanks to everyone for their help. I have learnt a lot since starting this
  project.

This site is really good... there is plenty of good information and i have
  already told 10 of my friends about this site they all agree after seeing
  it.

Keep up the good work.
Thanks once again.

-Lee


---------------------------------------------------------
Message Subject: One more question
Posted By:       Lee (mailto:)
Date/Time:       05-31-01 22:59
Message Link:    http://www.8052.com/forum/read.phtml?id=12093

Hi again... i have one more question before handing in my assignment.

I am to find out the cost of the processor in single quantity and in bulk.
  However, i have tried the links that Craig has given as well as other online
  shopping sites and doing a search on google but haven't been very
  successful...

Anyone know the round-about prices for the 8051 processor in single or bulk?




---------------------------------------------------------
Message Subject: RE: code for powerdown mode
Posted By:       Mohd Ridzuan Ranjit (mailto:Ranjit@...)
Date/Time:       05-31-01 01:52
Message Link:    http://www.8052.com/forum/read.phtml?id=12062

Hi Leo,

Does the Atmel 89C52 have such a feature implemented ?

Anyway thanks for the info.

Rgds


---------------------------------------------------------
Message Subject: RE: code for powerdown mode
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-31-01 08:54
Message Link:    http://www.8052.com/forum/read.phtml?id=12073

You mean: wake it up and ask, "are you asleep?"


---------------------------------------------------------
Message Subject: RE: Reserve Words
Posted By:       Prams (mailto:warhead128@...)
Date/Time:       05-31-01 06:16
Message Link:    http://www.8052.com/forum/read.phtml?id=12066

I'm using Keil Uvision 5.1 and I'm unable to use the '*' character.  What
  does it mean and what is it equivalent to??

Prams


---------------------------------------------------------
Message Subject: RE: Reserve Words
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-31-01 06:39
Message Link:    http://www.8052.com/forum/read.phtml?id=12067

  "c" or assembler?


---------------------------------------------------------
Message Subject: RE: Reserve Words
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-31-01 08:53
Message Link:    http://www.8052.com/forum/read.phtml?id=12071

uVision is simply an interface;
You must write your code in either Assembler or C, and use either the
  Assembler (A51.exe) or Compiler (C51.exe) to translate it. Consult the Keil
  documentation to discover their reserved symbols!

What are you trying to use '*' for - it's highly unlikely to be available as
  a symbol name, or even within a symbol name (in C, it's the pointer
  dereference operator and the multiplication operator).

BTW: any particular reason for uVision<b>51</b> - that's
  <b><i>waaaaaaaaaay</i></b> out of date!


---------------------------------------------------------
Message Subject: RE: Reserve Words
Posted By:       kalpak dabir (mailto:polsysdev@...)
Date/Time:       05-31-01 10:05
Message Link:    http://www.8052.com/forum/read.phtml?id=12075

what are you trying to do anyway, swear in assembly?! such symbols make code
  harder to read.


---------------------------------------------------------
Message Subject: RE: Interface 16550 USART to a BCC 8052
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-31-01 06:42
Message Link:    http://www.8052.com/forum/read.phtml?id=12068

   I do not know the MicroMint BCC 8052 but if it does not support the built
  in UART, buy another.

Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: Interface 16550 USART to a BCC 8052
Posted By:       Richard Houghton (mailto:richard.houghton@...)
Date/Time:       05-31-01 09:26
Message Link:    http://www.8052.com/forum/read.phtml?id=12074

Why not use a S/W Uart and forget the extra hardware ?


---------------------------------------------------------
Message Subject: RE: Interface 16550 USART to a BCC 8052
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-31-01 10:13
Message Link:    http://www.8052.com/forum/read.phtml?id=12076

It is worth to try if you can't use a software uart. I think in principle all
  you need is to map the 16C550 into the memory of the 8052 in a way that you
  can address the control registers of the uart as well. Then write to it as
  any external device with respect to the commands and timings in the
  datasheet:
  http://focus.ti.com/docs/prod/productfolder.jhtml?genericPartNumber=TL16C550
C


---------------------------------------------------------
Message Subject: RE: Phase angle, Duty Cycle
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-31-01 03:08
Message Link:    http://www.8052.com/forum/read.phtml?id=12065

"Phase shift of 180 degrees" really only has meaning for a steady-state
  sinewave. Do you mean you want a time delay of half a cycle?


---------------------------------------------------------
Message Subject: RE: Phase angle, Duty Cycle
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-31-01 06:44
Message Link:    http://www.8052.com/forum/read.phtml?id=12069

   &quot;we cannot compliment as duty cycle is not 50%&quot; what in the world
  do you mean ?  ANY signal can be complemented.


---------------------------------------------------------
Message Subject: RE: Phase angle, Duty Cycle
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-31-01 08:36
Message Link:    http://www.8052.com/forum/read.phtml?id=12070

With a steady-state sinewave, a 180-degree phase shift is indistinguishable
  from a polarity inversion (or "complement"); therefore lots of people make
  the (false) assumption that "180-degree phase shift" and "polarity
  inversion" are synonymous.

A signal with a duty cycle not equal to 50% is an excellent illustration of
  the why a "180-degree phase shift" and a "polarity inversion" are <b>not</b>
  synonymous!


---------------------------------------------------------
Message Subject: RE: Servo Control with the 80C251
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-31-01 03:03
Message Link:    http://www.8052.com/forum/read.phtml?id=12064

Try the 'Search' facility - I'm sure it's been discussed recently.


---------------------------------------------------------
Message Subject: RE: Servo Control with the 80C251
Posted By:       Stan Wilson (mailto:stanw@...)
Date/Time:       05-31-01 12:49
Message Link:    http://www.8052.com/forum/read.phtml?id=12081

John the F100 looks like a reasonable buy for the money.   Now you will need
  to learn how to write a few simple programs to run a robot.

I recommend the following books to start.

&quot;C and 8051&quot;, Vol I and Vol II by Thomas W. Schultz, publisher is
  Prentice Hall Amazon.com has both

Stan


---------------------------------------------------------
Message Subject: POP&amp;PUSH
Posted By:       Donatas (mailto:eziukas@...)
Date/Time:       05-31-01 10:28
Message Link:    http://www.8052.com/forum/read.phtml?id=12077

This question will sound very stupid, but I realy feel lost...

When I have to use POP and PUSH? And  what for?




---------------------------------------------------------
Message Subject: Franklin Documentation
Posted By:       Muhammad Omer (mailto:u970070@...)
Date/Time:       05-31-01 12:34
Message Link:    http://www.8052.com/forum/read.phtml?id=12080

Hi
Looking for the documentation of Kiel's/Franklin's Compiler V3.20 or in the
  nearabout. I have tried their site, they don't have it.



---------------------------------------------------------
Message Subject: RE: Franklin Documentation
Posted By:       tong_tang@... (mailto:)
Date/Time:       05-31-01 15:51
Message Link:    http://www.8052.com/forum/read.phtml?id=12083

you it verry verry old
this present my use keil6.10 aready !
about book or document you can use
keil5.2 or keil6.0 at www.keil.com


i teach and traning 8051 with c of keil6.10
at http://go.to/c51

this sorry this web is for thailand only


---------------------------------------------------------
Message Subject: Timer input de bounce
Posted By:       V.DURGAI DASS (mailto:durgaidass@...)
Date/Time:       05-31-01 22:42
Message Link:    http://www.8052.com/forum/read.phtml?id=12091

Hi all,
I am using the 8031 timer1 in count mode to count the closures of a read
  switch. The frequency is 200 pulses per second. When i give the input from a
  pulse generator to my kit, the result is repeatetivly correct. But when i
  connect the read switch input, the result is not repeating. It varies
  between +/- 2Hz (10 pulses in 5 seconds).But the same reed switch if
  connected to a ICM 7217 based counter, the result is repeating. The problem
  with my 8031 kit,I persume is because of reed switch debounce. How do
  introduse debouncing to the timer when it works in external count mode.

D.Dass


-------------------------------------------------------

--
Fausto Marzoli
8052 Group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.



Saluti,

--
Fausto Marzoli
8052 group Moderator


---------------------------------------------------------
Message Subject: XT Keyboard
Posted By:       Oleg Gonopolskiy (mailto:olgon@...)
Date/Time:       05-30-01 15:06
Message Link:    http://www.8052.com/forum/read.phtml?id=12056

Could someone post where I can find C code to send XT keybord serial strings
  "A","B","C" from 8052 to PC? I havent much
  luck to write own routine because PC  keybord port wait for some reset
  characters from 8052 ect...


---------------------------------------------------------
Message Subject: RE:  4 digit led multiplexed display
Posted By:       j.parimala (mailto:jparimala@...)
Date/Time:       05-30-01 05:46
Message Link:    http://www.8052.com/forum/read.phtml?id=12038

Kindly send me the efficient way of multiplexing 6 led displays with an 8 bit
  port,of 8751


---------------------------------------------------------
Message Subject: RE: which development tool to buy???
Posted By:       Girish Ranade (mailto:gsr@...)
Date/Time:       05-30-01 06:33
Message Link:    http://www.8052.com/forum/read.phtml?id=12039

If you are a professional you must have In Circuit Emulator and not the kit.
  It is even better than simulator (my openion). Girish



---------------------------------------------------------
Message Subject: RE: which development tool to buy???
Posted By:       Oleg Gonopolskiy (mailto:olgon@...)
Date/Time:       05-30-01 15:15
Message Link:    http://www.8052.com/forum/read.phtml?id=12057

Keil is good for me.


---------------------------------------------------------
Message Subject: This might help
Posted By:       Joe Carbola (mailto:Joec@...)
Date/Time:       05-30-01 07:08
Message Link:    http://www.8052.com/forum/read.phtml?id=12046

do_msg: mov     dptr, #mesg1
               lcall   pstr
               lcall   newline
               mov     dptr, #mesg2
               lcall   pstr
               ret
       mesg1:  .db     "This is a test messag", 'e'+128
       mesg2:  .db     "testing:  1.. 2.. 3..", 0



---------------------------------------------------------
Message Subject: RE: HELP MT8880 connect to Telephoneline ???
Posted By:       Gil Simon (mailto:gil_simon_2k@...)
Date/Time:       05-30-01 02:16
Message Link:    http://www.8052.com/forum/read.phtml?id=12030

Hi Armbruster,

Yeh, that's right, use an old one to take a transformer out.

You connect them directly to line with 70volts DC it won't burn, at least not
  in my case.

Have fun

Simon


---------------------------------------------------------
Message Subject: RE: Gil - MT8880 connect to phoneline
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-30-01 06:53
Message Link:    http://www.8052.com/forum/read.phtml?id=12042

Gil,

You have just described a SLIC!

OK, not a full-feature, all-singing, all-dancing, bells-&-whistles SLIC, but
  it <b><i>is</i></b> still a "SLIC" - <b>S</b>ubscriber <b>L</b>ine
  <b>I</b>nterface <b>C</b>ircuit!

BTW: in some territories, connecting unapproved (including homebrew)
  equipment to the Public telephone system is <b>ILLEGAL</b>. And with 70VAC,
  it's not to be taken lightly anyway!


---------------------------------------------------------
Message Subject: RE: 8051 C Compiler Design
Posted By:       Victor Wolff Collin (mailto:vwc.ez@...)
Date/Time:       05-30-01 09:40
Message Link:    http://www.8052.com/forum/read.phtml?id=12049

If you really want to write a compiler, a good start is the
  &quot;small-C&quot;, a C compiler writtten in the C language, originally
  written for the intel 8080 processor. The source code is available on the
  internet. Later, this code was ported to (both) Motorola 68000 and 68HC11
  processors.  Just look for &quot;+small +C +compiler&quot;   (a search in
  yahoo will find about 170 thousand matches :o)  )


---------------------------------------------------------
Message Subject: RE: AT89S8252 flash problem
Posted By:       Karsten Krause (mailto:psyphy@...)
Date/Time:       05-30-01 03:07
Message Link:    http://www.8052.com/forum/read.phtml?id=12033

Thanks a lot so far,
now Peter D. threw in some suggestions I´d like to reply to:

&gt; please check:
&gt; 1.
&gt; Was something connected to the SPI ports (P1.5, P1.6, P1.7), which &gt;
  can generate pulses ? &gt; Maybe it can help to use pull up resistors.

On P1 I have a couple of keys, connected via 15cm (6 in.) non shielded flat
  cable, attached ferrite bar, nothing else.

&gt; 2.
&gt; Was the reset circuit right selected for the minimum VCC voltage of &gt;
  the micro ?

For this application I chose a MAX81 SEURT (3.0V / 200ms) for different
  reasons. The app is battery driven and I better don´t use a resetter above
4.1 V. Between that and 3V positive resetters are hard to find

&gt;3.
&gt; Was the crystal working good, e.g. start to oscillate fast enough until
  &gt; reset was done ?

The crystals in the 5 boards I built in the meantime look allright. The
resetter allows them 200ms to wake up which should be fine.

&gt;4.
&gt;Try to set the lock bits or disable the RCEN fuse to see, if the flash
  &gt;was erased nevertheless

I did that few days ago, til now no other error has ocurred. But that
somtimes took WEEKS to show up.

&gt;5.
&gt;Was the whole flash erased or only some bytes ?

Only some bytes at different locations.


PS: I just changed the layout a little and built up a new board with no
errors so far. Let´s see. Thanks to Jaceks input I´ll be looking
forward to get the newest revision &quot;T&quot;.

For another application I have programmed and used some 1000+
of Atmels 89C2051 (no exclusive reset circuit used).
NOT A SINGLE defective sample or strange behavior in 9 months. Concerning my
  prototypes I give them a REAL bad time.

Karsten Krause


---------------------------------------------------------
Message Subject: RE: AT89S8252 flash problem
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-30-01 06:52
Message Link:    http://www.8052.com/forum/read.phtml?id=12041

   Just one question: has anyone seen this problem with the security bits set?

Erik


---------------------------------------------------------
Message Subject: RE: Delay code??
Posted By:       Gil Simon (mailto:gil_simon_2k@...)
Date/Time:       05-30-01 02:28
Message Link:    http://www.8052.com/forum/read.phtml?id=12031

Hi Rio,

You said,

"But remember, in many applications SW delays are not the best option!."

Can you tell us what is best option to have delays in the code, please.


Simon


---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-30-01 06:59
Message Link:    http://www.8052.com/forum/read.phtml?id=12043

   oooooooooooh, 5V single ended control lines next to a 3 phase motor.
  NOISE. First make your software react to input only if it is the same for at
  least 100 mSec.  The second thing to try, which will not upset your design
  too much is to connect 100 ohms from +5 to the port pin, a .1 uF capacitor
  to ground and the switch between the pin and ground and a mammoth capacitor
  (100uF tantalum minimum) from the +5 side of the resistor to ground.


---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-30-01 07:46
Message Link:    http://www.8052.com/forum/read.phtml?id=12048

I had the counting inputs connected directly to a PALCE22V10, which is a
  high-impedance CMOS input. This input was very sensitive to noise as it
  appeared later on. I had my counter input set up with a 4K7 series resistor
  to the base of a BC337 and a 4K7 resistor from base to ground. The emitter
  connected to ground and the collector connected to VCC via a 1K resistor.
  The junction of the collector and the 1K I used to feed the PALCE which fed
  a 71054 (PIT). I could not use a capacitor in this application because I was
  counting pulses and because the application should be able to count at high
  speeds any kind of filtering would decrease the performance. But in your
  case this circuit in combination with what Erik suggest could very well do
  the "trick". Or maybe only Erik's suggestion would be sufficiant.


---------------------------------------------------------
Message Subject: RE: Atmel revision
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-30-01 03:41
Message Link:    http://www.8052.com/forum/read.phtml?id=12035

Thank you Peter, you are right. I have got complete information from USA
  Atmel's office. Maybe it will be usefull for someone:

1.  AT89S8252 : Back side Markings
PDIP: e.g
   Line 1  L--->R  0A1875- 19552S
   Line 2  L--->R  1KOREA-H 0A0012

The mask # 19552,Rev-S,0012=is date code for testing in production.

2. For PLCC e.g  0A1875S
    AT19552
    1KOREA
    0A0012   H
Again you see line-1,this is Rev-S again.

3.For TQFP e.g 0A1875
    19552S
    1KOREA
    0A0012   H
Here we have line-2,which has Rev-S again.


---------------------------------------------------------
Message Subject: RE: Craig !!
Posted By:       Gil Simon (mailto:gil_simon_2k@...)
Date/Time:       05-30-01 02:47
Message Link:    http://www.8052.com/forum/read.phtml?id=12032

Hi Craig,

Its not the fault of students like Lee, at all.

I don't understand what kind of instructers are there who just give an oder
  to do a project.

From the questions of Lee, it seems he is at the basics and the instructer is
  just concerned with the output result.

I suggest whenever we get a post like that, we should though help out but
  also ask the person to talk to his/her instructer as well to do his part of
  the job.

Simon


---------------------------------------------------------
Message Subject: If in doubt, ASK!
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-30-01 04:05
Message Link:    http://www.8052.com/forum/read.phtml?id=12036

Lee,

The <b>first</b> thing you <b><i>must</i></b> do if you are set a question
  that you don't understand is to <b>talk to your teacher/lecturer/tutor!</b>
  It's unwise to try to guess or, worse, ask someone else to guess what the
  question means - you could waste your time answering the wrong question!
  This applies equally in industry: if the project/product requirements are
  not clearly stated, get them clarified <b><i>before</i></b> you start -
  otherwise you'll end up with a product that the boss/customer doesn't
  actually want!


---------------------------------------------------------
Message Subject: RE: still confused
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-30-01 04:22
Message Link:    http://www.8052.com/forum/read.phtml?id=12037

Note that <i>"PowerPC"</i> also refers to a <i>family</i> of processors - see
  the <i>PowerPC Roadmap</i> on the Motorola site:
  http://e-www.motorola.com/webapp/sps/technology/tech_overview.jsp?catId=M983
989030230


---------------------------------------------------------
Message Subject: RE: Information required on 8051
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-30-01 07:05
Message Link:    http://www.8052.com/forum/read.phtml?id=12044

   For an example of one manufactureres &quot;family&quot; try
  http://www-us.semiconductors.philips.com/mcu/products/selguides/.  For
  generic information on the family get the 80C51 documents at
  http://www-us.semiconductors.philips.com/mcu/products/selguides/

Hope this helps,

Erik


---------------------------------------------------------
Message Subject: RE: Information required on 8051
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-30-01 07:07
Message Link:    http://www.8052.com/forum/read.phtml?id=12045

   Sorry, it is still early EDT. The 80C51_FAM documents, you will only need
  those 3.

Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: thanks again
Posted By:       sanjeev kumar (mailto:sanjeevkumar_abc@...)
Date/Time:       05-30-01 12:14
Message Link:    http://www.8052.com/forum/read.phtml?id=12053

Lee wrote:
-------------------------------
Oh,part of my project is to design a fridge temperature controller. ie.
  program the temp in the keypad and the fridge will keep at that temp.
  -------------------------------

Hi ,
so you want to make a thermostate no problem but first goto
  www.specs.de/~danni   our very own peter's site and practice with some
  projects then goto Ben Zijlastras site http://members.home.nl/bzijlstra then
  come back with more questions .

good luck

sanjeev





---------------------------------------------------------
Message Subject: Help - 8952 External RAM
Posted By:       T S Rajesh (mailto:tsrajesh@...)
Date/Time:       05-30-01 00:38
Message Link:    http://www.8052.com/forum/read.phtml?id=12029

I want to use 64K of external RAM with an 89C52, but want to use the internal
  8K Flash for program memory. (I don't want to use external flash for
  program). Can anyone help me how to do it?. Thanks.


---------------------------------------------------------
Message Subject: RE: Help - 8952 External RAM
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-30-01 03:35
Message Link:    http://www.8052.com/forum/read.phtml?id=12034

Shouldn't be a problem, as the code and data spaces are separate.

As far as the 8052 "core" is concerned, the FLASH is still "external" - it
  just so happens that the chip vendor has integrated it within the same
  package. The device datasheet should explain how to use it.




---------------------------------------------------------
Message Subject: code for powerdown mode
Posted By:       Jonnny 5 (mailto:warhead128@...)
Date/Time:       05-30-01 06:40
Message Link:    http://www.8052.com/forum/read.phtml?id=12040

i need code for powerdown mode which can run an interupt and show that its
  usiing less power


---------------------------------------------------------
Message Subject: RE: code for powerdown mode
Posted By:       sanjeev kumar (mailto:sanjeevkumar_abc@...)
Date/Time:       05-30-01 11:54
Message Link:    http://www.8052.com/forum/read.phtml?id=12051

hi,
There is absolutely no problem in remaining TIM we are not going to harm you
  anyway :) .BTW if your processor goes in powerdown mode how will your
  program run???????????????? try detecting ALE pulses they will dissapear
  from your CRO ?

sanjeev


---------------------------------------------------------
Message Subject: RE: code for powerdown mode
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-30-01 14:15
Message Link:    http://www.8052.com/forum/read.phtml?id=12054

   this is derivative dependent, look at page 10 of
  http://www-us6.semiconductors.com/acrobat/datasheets/P89C51RB2_P89C51RC2_P89
C51RD2_7.pdf for info on one version.

Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: code for powerdown mode
Posted By:       Mohd Ridzuan Ranjit (mailto:Ranjit@...)
Date/Time:       05-30-01 22:18
Message Link:    http://www.8052.com/forum/read.phtml?id=12058

Hi Jonny,

To my understanding the 80XX chips will not be awaken by an interupt. Once u
  have power down it, the only way to wake it up is by a hardware RESET.

However if you are worried about power and want to reduce power consumption,
  try putting the chip into standyby mode. This will reduce power, and yet
  allows it to be awaken when a interupt is detected.

Wish you the best.

Chow.



---------------------------------------------------------
Message Subject: RE: code for powerdown mode
Posted By:       Leo Paul (mailto:leo_paul@...)
Date/Time:       05-30-01 23:07
Message Link:    http://www.8052.com/forum/read.phtml?id=12060

Hi Jonny 5

As Erik, pointed out there are derivatives of 8052, that can wake from
power down mode from interrupts other than hard reset.

Ranjit,

yes, original plain vanilas are like you said - exit from power down is only
  by hard reset. But not anymore with new derivatives.


---------------------------------------------------------
Message Subject: Reserve Words
Posted By:       Prams (mailto:warhead128@...)
Date/Time:       05-30-01 07:35
Message Link:    http://www.8052.com/forum/read.phtml?id=12047

Can anyone tell me if the asterik (*) is a reserve word for the 8051??

Prams


---------------------------------------------------------
Message Subject: RE: Reserve Words
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-30-01 10:40
Message Link:    http://www.8052.com/forum/read.phtml?id=12050

   not for the '51, but for some compilers and assemblers it is.

Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: Reserve Words
Posted By:       sanjeev kumar (mailto:sanjeevkumar_abc@...)
Date/Time:       05-30-01 11:56
Message Link:    http://www.8052.com/forum/read.phtml?id=12052

Hi,
yes it depends on the assembler you are using isn't it.


---------------------------------------------------------
Message Subject: Interface 16550 USART to a BCC 8052
Posted By:       Ross Lunan (mailto:arl314@...)
Date/Time:       05-30-01 14:54
Message Link:    http://www.8052.com/forum/read.phtml?id=12055

Any references to existing descriptions of hardware connections and Basic or
  assembler code to add a USART such as the very common 16550 chip to a
  MicroMint BCC 8052 board? Can this USART be interfaced to the 8255 I/O ports
  (8 bits data + few control bits)? Only need 2400 bit/s and do not want to
  use the Console I/F


---------------------------------------------------------
Message Subject: Phase angle, Duty Cycle
Posted By:       ankas (mailto:ankas@...)
Date/Time:       05-30-01 22:23
Message Link:    http://www.8052.com/forum/read.phtml?id=12059

Hi,
if we have a signal with duty cycle that is not 50% in  a port pin say
p0.0 .and we want a signal  phase shifted to say  180 degrees at
p0.1.how to do it ?
we cannot compliment as duty cycle is not
50%.so how to phase shift it?

ankas


---------------------------------------------------------
Message Subject: Servo Control with the 80C251
Posted By:       John (mailto:hobby_robotics@...)
Date/Time:       05-30-01 23:47
Message Link:    http://www.8052.com/forum/read.phtml?id=12061

I'm using an F100-11 from TECEL(www.tecel.com). Can any body please advice me
  on how to control a servo with one of the timers?

-------------------------------------------------------

--
Fausto Marzoli
8052 group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.



Saluti,

--
Fausto Marzoli
8052 group Moderator


---------------------------------------------------------
Message Subject: DTMF generator
Posted By:       Rajeswara rao (mailto:rajeshp@...)
Date/Time:       05-29-01 05:01
Message Link:    http://www.8052.com/forum/read.phtml?id=12004

Hai e's,

  Iam working with micro controller to generate DTMF and tx through telephone
  line to give a ring at another telephone. I tried with mt8880 iam able
  generate DTMF but i want to know how to interface with line. Could u sggest
  me with u'r experiance.

regaurds
rajesh


---------------------------------------------------------
Message Subject: RE: 87C752 serial between 2 micros
Posted By:       SNAKES (mailto:)
Date/Time:       05-29-01 06:33
Message Link:    http://www.8052.com/forum/read.phtml?id=12006

EWW


---------------------------------------------------------
Message Subject: RE: 87C752 serial between 2 micros
Posted By:       Prams (mailto:warhead128@...)
Date/Time:       05-29-01 06:45
Message Link:    http://www.8052.com/forum/read.phtml?id=12007

Aright, I found out that i initialized SCON incorrectly for the receiving
  end.  Here's the code initializing SCON, TCON, and TMOD and the code for the
  receiving end:

Mov TMOD, #00010000B
MOV TCON, #00000000B
MOV SCON, #00010000B

JNB RI, $
CLR RI
MOV A, SBUF
**Q:  The program only monitors RI for receiving??

The Code for the Transmitting side is:
MOV TMOD, #00010000B
MOV TCON, #00000000B
MOV SCON, #00001000B

MOV SBUF, R0
HOLD: JNB TI, HOLD
CLR TI

Is this code sufficient to transmit data between two micros?????

Prams


---------------------------------------------------------
Message Subject: RE: 87C752 serial between 2 micros
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-29-01 09:28
Message Link:    http://www.8052.com/forum/read.phtml?id=12010

   You are absolutotally lost.  READ the register specs in the 80C51_fam
  documents at
  http://www-us.semiconductors.philips.com/handbook/various_66.html and THEN,
  if you still have problems, come back.

Erik


---------------------------------------------------------
Message Subject: RE: Alfredo del Rio
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-29-01 15:00
Message Link:    http://www.8052.com/forum/read.phtml?id=12015

Yes, it is true. The same way you program FLASH, you can program EEPROM. So
  why not? Look at Atmel's web site (AT89S-LS8252 errata.pdf). It is a
  professional forum, I think. Isn't it?


---------------------------------------------------------
Message Subject: RE: AT89S8252 flash problem
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-29-01 16:41
Message Link:    http://www.8052.com/forum/read.phtml?id=12018

Hi Karsten,

please check:

1.
Was something connected to the SPI ports (P1.5, P1.6, P1.7), which can
  generate pulses ? Maybe it can help to use pull up resistors.

2.
Was the reset circuit right selected for the minimum VCC voltage of the micro
  ?

3.
Was the crystal working good, e.g. start to oscillate fast enough until reset
  was done ?

4.
Try to set the lock bits or disable the RCEN fuse to see, if the flash was
  erased nevertheless

5.
Was the whole flash erased or only some bytes ?


Peter



---------------------------------------------------------
Message Subject: bin to ASM
Posted By:       lkhagva (mailto:c_lkhagva@...)
Date/Time:       05-29-01 04:16
Message Link:    http://www.8052.com/forum/read.phtml?id=12002

I need dis-assembler for 51.
need bin to asm converter.
help me!



---------------------------------------------------------
Message Subject: RE: bin to ASM
Posted By:       Alfredo del Rio (mailto:ario@...)
Date/Time:       05-29-01 04:50
Message Link:    http://www.8052.com/forum/read.phtml?id=12003

Hello Ikhagva,

You can find some free disassemblers for the 8051 in the web, that run under
  MS-DOS.

I have developed one (UVIDES51), which is now part of the UVI51 environment.
  If you want, I can send it to your mail address. Though I think that mine is
  not the best, for example it does not replace SFR addresses by symbols.



---------------------------------------------------------
Message Subject: RE: bin to ASM
Posted By:       erik malund (mailto:malund@...)
Date/Time:       05-29-01 09:35
Message Link:    http://www.8052.com/forum/read.phtml?id=12011

http://www-us.semiconductors.philips.com/mcu/download/80c51/assemblers/

have fun,

Erik


---------------------------------------------------------
Message Subject: code for sleep mode
Posted By:       tim (mailto:krackh0re@...)
Date/Time:       05-29-01 06:33
Message Link:    http://www.8052.com/forum/read.phtml?id=12005

i need it to show its in sleep mode also i need a good introduction on it


---------------------------------------------------------
Message Subject: RE: code for sleep mode
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-29-01 11:39
Message Link:    http://www.8052.com/forum/read.phtml?id=12013

What do you mean, <i>"show its in sleep mode?"</i>

For an introduction - read the device data sheet.


---------------------------------------------------------
Message Subject: RE: code for sleep mode
Posted By:       sanjeev kumar (mailto:sanjeevkumar_abc@...)
Date/Time:       05-29-01 12:00
Message Link:    http://www.8052.com/forum/read.phtml?id=12014

Hi,
I think technically its not the sleep mode but the powerdown mode.If your
  processor is in powerdown mode you can only revive it by resetting it the
  system clock stops completely in powerdown mode.

sanjeev








---------------------------------------------------------
Message Subject: RE: code for sleep mode
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-29-01 18:17
Message Link:    http://www.8052.com/forum/read.phtml?id=12019

Depending on which particular variant you have, it could have "power-down"
  and "idle" modes - "power-down" stops more clocks (therefore, saves more
  power) than "idle"

Different manufacturers may choose different names.

See your datasheet.


---------------------------------------------------------
Message Subject: error in driving 3 phase motor
Posted By:       ridwan efendi (mailto:ridvvan@...)
Date/Time:       05-29-01 07:09
Message Link:    http://www.8052.com/forum/read.phtml?id=12008

I want to drive a 3 phase hoist motor. it work very simple, just rotate left
  ,stop than rigt (depend on the order there are 3 push button ; left,right
  and stop). It seems  work very good when i simulate it without the motor
  (just drive the relay). but the problem arises when I put the hoist motor.
first I push the button 'left', the motor rotate to the left (that's a good
  start) then I push the button 'stop', the motor stop, suddenly it rotate
  again (randomly, may be to the right, may be left) I repeat this (rotate
  left then stop) for about 20 times, the errors occured 16 times !!! I check
  the program... that's nothing wrong (i hope)


I courious about the electromagnetic wave that produced by the hoist motor,
is that true???
can somebody tell me why this is happen?
how to solve it??

thanks,

Ridwan Efendi



---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       Bert Sesam (mailto:Sesam_Bert@...)
Date/Time:       05-29-01 07:59
Message Link:    http://www.8052.com/forum/read.phtml?id=12009

Are you sure that ALL 3 PHASES are disconnected ?

A 3 phase motor can/may run with only 2 fases connected ...

This may damage your motor !!

Bert


---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-29-01 10:34
Message Link:    http://www.8052.com/forum/read.phtml?id=12012

Do you have any sensors attached to your system telling something about the
  movement of the motor? If you are monitoring those it could well be that the
  electromagnetic field of either the motor or the relais which drive them
  disturb either your program or the sensors. I can speak from experience, I
  had a system counting pulses over 25 meters at about 700 pulses per meter.
  Also a 3-phase 380V motor going left and right and in two different speeds.
  Everytime the distance was run the pulse-count was different (on my
  controllerboard). Then I built an external counter with CD4029 etc and it
  worked perfectly!!! Only 1 pulse difference per run. About 17,320 pulses
  each time. I went nuts. Finally, desperately I changed the input on my
  application (TTL) to the same I had built in my counter (transistors BC337)
  and problem solved. The relays, together with the motor caused many spikes
  that influenced the working of the application. Hope this is of some help.

Aad Sieraad


---------------------------------------------------------
Message Subject: RE: error in driving 3 phase motor
Posted By:       ridwan efandi (mailto:ridvvan@...)
Date/Time:       05-29-01 22:15
Message Link:    http://www.8052.com/forum/read.phtml?id=12022

Mr Sesam, I'm sure the 3 phase were already disconected (there was a moment
  when all the 2 relays are off, this means the motor is totaly disconected)



Mr Sieraad, I'm very interested in your experience. It seems there are many
  similarity in our  case.To be more percise, the motor is used to lift
  something heavy from one floor to another (in 4 story house, and not used to
  lift human). In each floor there is a button to call the box (which is used
  to lift something)and also a limit switch that tell the mcu , the box has
  already arrived.

the push button and the limit switch work only to input 5 v DC to the input
  port of the mcu (when it is pressed, 5v is conected to the mcu) Mr Sieraad,
  You solved the problem by changing the method of inputting data, could you
  tell me the detail please??



thanks



ridwan


---------------------------------------------------------
Message Subject: Atmel revision
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-29-01 15:10
Message Link:    http://www.8052.com/forum/read.phtml?id=12016

In revision "S" or earlier AT89S8252 and AT89LS8252, inadvertent writes to
  EEPROM or FLASH memory can occur. The solution is to use revision "T" or
  later. Is anybody knowing, how to recognize AT's revision? I have asked
  local ATMEL's office (the first time about a 2 months), but they haven't
  answered me yet.

I have been using:
AT89S8252
24PI
0029

I have asked local distributors, too. They also don't know, how to recognize
  the revision of micro. It is very urgent, help me please.



---------------------------------------------------------
Message Subject: RE: Atmel revision
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-29-01 16:28
Message Link:    http://www.8052.com/forum/read.phtml?id=12017

On a DIL-40 case I have seen 2 lines off numbers also on the back side. The
  first line was with a letter on the end, maybe this was the revision.


Peter


---------------------------------------------------------
Message Subject: Information required on 8051
Posted By:       Lee (mailto:fu_li2@...)
Date/Time:       05-29-01 21:36
Message Link:    http://www.8052.com/forum/read.phtml?id=12020

Hi there, I'm trying to find the following information on the 8051
  processor...can anyone help me out? Any links would be appreciated.

The cost of the processor in single quantity and in bulk
The clock speed of the microprocessor
The Register structure
The number of data bits
The number of address bits
The addressable range
The addressing modes
The instruction set
The power consumption




---------------------------------------------------------
Message Subject: RE: Information required on 8051
Posted By:       Craig Steiner (mailto:csteiner@...)
Date/Time:       05-29-01 21:53
Message Link:    http://www.8052.com/forum/read.phtml?id=12021

<I>The cost of the processor in single quantity and in bulk </I>

Check electronics stores, or online at places such as <A
  HREF="http://www.jameco.com">Jameco</A>.

The price depends on which model you purchase.  There are hundreds of
  different models from dozens of different semiconductor companies.  Check
  the <A HREF="http://www.8052.com/chips.phtml">chips page</A> for a partial
  list of 8052-compatible microcontrollers.

<I>The clock speed of the microprocessor</I>

Check the datasheet for the MCU that you decide on.

<I>The Register structure</I>

Check here on the site at <A HREF="http://www.8052.com/tut8051.phtml">8051
  tutorial</A>.  Further information can be found in the datasheet of the part
  you choose.

<I>The number of data bits</I>

8.

<I>The number of address bits</I>

Depends on the part you choose.  Usually 16-bits which are multiplexed with
  the data bits.

<I>The addressable range</I>

2^16 = 64k.

<I>The addressing modes</I>

See the <A HREF="http://www.8052.com/tutaddr.phtml">addressing modes
  tutorial</A> here on this site.

<I>The instruction set</I>

Check the <A HREF="http://www.8052.com/set8051.phtml">instruction set</A>
  here on this site.

<I>The power consumption</I>

See the datasheet for the part you choose.

It seems to me you are asking us questions without having tried to find the
  answers yourself.  You know better than us what your requirements are so
  first choose a part, read the datasheet, read the tutorial on this site, and
  if you still have any questions feel free to let us know.

  Craig Steiner



---------------------------------------------------------
Message Subject: still confused
Posted By:       Lee (mailto:fu_li2@...)
Date/Time:       05-29-01 22:21
Message Link:    http://www.8052.com/forum/read.phtml?id=12023

Thanks for your reply Craig. And yes i HAVE been doing some research on all
  the above. However, i'm still having trouble understanding what the
  difference is between all these different models. My requirement is to
  &quot;compare the 8051 processor(small) and Power PC processor(large)-where
  the processor applies to a FAMILY of processors, you are required to
  describe the common properties across the family and chose one variant to
  answer more specific questions&quot;. Now what i don't understand is this. t
  just says the 8051 processor... but there are so many processors. What does
  it mean by FAMILY of processor? does this mean, the MAIN characteristics of
  all the different models of 8051?

Sorry, bout my earlier post... it should have ONLY been these topics below
  which i needed help on. I forgot to delete the other ones after the copy and
  paste...

1)The cost of the processor in single quantity and in bulk .
2)The clock speed of the microprocessor .
3)The Register structure.
4)The power consumption.

Thanks again..


---------------------------------------------------------
Message Subject: RE: still confused
Posted By:       Craig Steiner (mailto:csteiner@...)
Date/Time:       05-29-01 22:33
Message Link:    http://www.8052.com/forum/read.phtml?id=12024

Is this a school assignment?

The "Family" they are talking about is the family of hundreds of 8052
  derivatives that I mentioned in my last post.  All these chips are a
  "family" because they all contain the 8052 "core."  This means they all
  share the characteristics contained in the <A
  HREF="http://www.8052.com/tut8051.phtml">8051 tutorial</A>.

In addition, each "member of the family" (derivative chip) has its own
  features and specifications.  Some chips have A/D converters, others have
  features that allow them to be connected to USB ports, others include
  on-board Flash memory, etc.  Which member of the family you choose depends
  on the features you need.  But regardless of which chip you use, it will
  still conform to the 8052 core which is explained in detailed in the
  tutorial mentioned above.

In your questions above, all four depend on which derivative chip you select.
   If this is just a school assignment and it doesn't matter which chip you
  select, just select any chip from <A
  HREF="http://www.8052.com/chips.phtml">the chips page</A>, read the
  datasheet, and get your information from that.  All the chips on this page
  are part of the "8052 family."  i.e., they contain the 8052 core and are
  thus compatible with the 8052.

  Craig Steiner



---------------------------------------------------------
Message Subject: RE: thanks again
Posted By:       Lee (mailto:fu_li2@...)
Date/Time:       05-29-01 22:45
Message Link:    http://www.8052.com/forum/read.phtml?id=12025

Thanks again Craig. And yes this is a school assignment. I've spent the last
  two days on google.com and have found HEAPS of information but the more i
  read the more i confuse myself.

In this case you're saying that the 8051 is a derivative of the 8052 right?
  So all the tutorials for the 8052 should apply to the 8051 then?

And what do you mean by datasheet?We have not covered this in class? How do i
  read one of these sheets?! Are those .pdf files on the chips page the
  datasheets? I had a look at those a few days ago and it just scared and
  confused me even more! Is there an easy way to interpret these datasheets?

Cheers...


---------------------------------------------------------
Message Subject: RE: thanks again
Posted By:       Craig Steiner (mailto:csteiner@...)
Date/Time:       05-29-01 23:16
Message Link:    http://www.8052.com/forum/read.phtml?id=12026

The "base model" is 8031. That is really what's described in the online
  tutorial.  Everything else is a derivative of that.

Datasheets are documents that give the specifics of any given IC.  Yes, they
  are the PDF files that are linked to from the chips page.  The PDFs are not
  hard to understand but they do assume some level of knowledge of the
  architecture and electronics.  If your class is referencing clock speeds and
  power consumption I would think the datasheets would not be that foreign to
  you...

What is your class?  If it's extremely basic you might want to check out <A
  HREF="http://www.howstuffworks.com/microcontroller.htm">How Stuff Works:
  Microcontrollers</A>.  It talks about how/what microcontrollers are in very
  easy-to-understand terms, for the non-computer non-engineer type of person.
  That might help you get a grasp on some of the topics that this site assumes
  you already know.

  Craig Steiner



---------------------------------------------------------
Message Subject: RE: thanks again
Posted By:       Lee (mailto:fu_li2@...)
Date/Time:       05-29-01 23:26
Message Link:    http://www.8052.com/forum/read.phtml?id=12027

Thanks Craig.. you have been a great help.

Oh,part of my project is to design a fridge temperature controller. ie.
  program the temp in the keypad and the fridge will keep at that temp.

Do you kow what kind of temperature reader i can use with the 8051?

thanks


---------------------------------------------------------
Message Subject: RE: thanks again
Posted By:       Lee (mailto:fu_li2@...)
Date/Time:       05-29-01 23:38
Message Link:    http://www.8052.com/forum/read.phtml?id=12028

Never mind... i found one.. the DS1620.

thanks anyway...


-------------------------------------------------------

--
Fausto Marzoli
8052 group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.



Saluti,

--
Fausto Marzoli
8052 group Moderator


---------------------------------------------------------
Message Subject: RE: Emulating PC Serial Mouse
Posted By:       Reinhard Dämon (mailto:r.daemon@...)
Date/Time:       05-28-01 04:29
Message Link:    http://www.8052.com/forum/read.phtml?id=11993

try also:


  http://panda.cs.ndsu.nodak.edu/~achapwes/PICmicro/mouse/mouse.html


  http://govschl.ndsu.nodak.edu/~achapwes/PICmicro/PS2/ps2.htm

                    http://www.nti1.com/ps2-prots.html


---------------------------------------------------------
Message Subject: RE: P2mouse to 8051
Posted By:       Reinhard Dämon (mailto:r.daemon@...)
Date/Time:       05-28-01 04:26
Message Link:    http://www.8052.com/forum/read.phtml?id=11992

try also:

http://panda.cs.ndsu.nodak.edu/~achapwes/PICmicro/mouse/mouse.html

http://govschl.ndsu.nodak.edu/~achapwes/PICmicro/PS2/ps2.htm

http://www.nti1.com/ps2-prots.html




---------------------------------------------------------
Message Subject: RE: RS232 to RS485 converter for RTS/ CTS
Posted By:       Vithal Pai (mailto:vithalpai@...)
Date/Time:       05-28-01 02:10
Message Link:    http://www.8052.com/forum/read.phtml?id=11988

Thank you, Erik. I will have to go for full duplex operation. Here I will
  have to use 2 nos. of MAX 485 chips for full duplex operation.

with best regards

Vithal Pai


---------------------------------------------------------
Message Subject: RE: HELP MT8880 connect to Telephoneline ???
Posted By:       Gil Simon (mailto:gil_simon_2k@...)
Date/Time:       05-28-01 02:47
Message Link:    http://www.8052.com/forum/read.phtml?id=11989

Hi Armbuster,

Do not confuse. You don't need a SLIC if you are going to make a single unit
  application and not a complete centralized office network.

I assume you want to make just a dialer.

I also assume you want to receive the rings also.

So lets proceed as follows:

Take a transformer out from a screwed one modem. (or buy a 56k modem and
  screw it)

Now for ring detection use a line capacitor (330nF/400V) and brige rectifier
  and current limiting resistor (22K/1Watt). This DC output you give straight
  to an opto 4N35. The opto will give out put when ring AC voltage / signal is
  present in the line. Use the output of opto as you wish. One appropriate use
  is to go off hook after counting the desired number of rings.

Now for off hook, connect one side of the transformer to the line in
  parallel. Measure the voltage accross the line. It should be equal to the
  off hook with a normal telephone set in your country. If the voltage drop is
  too much then connect 2watt resistor in series of the transformer with the
  line. The common values you may select between 100 ohms to 500 ohms,
  depends. Now you have a proper off hook.

And don't forget that transformer should connect and disconnect to the line
  through a relay switched from your micro.

Now DTMF. Connect one leg of the transformer of the other side to the ground
  of your circuit.

Tie up together the two signals namely DTMF/CP and DTMF OUTPUT on page 4-43
  of the data sheet of MT8880.

Connect this tie up to the second leg of the transformer.

So, with the above your hardware layout is complete. You can refine it to
  suite your needs.

If you have any problem with the software, we can talk.

Don't have any fun, go straight to the work and work harder.

Simon








---------------------------------------------------------
Message Subject: RE: HELP MT8880 connect to Telephoneline ???
Posted By:       Jesper Henriksen (mailto:jesper792@...)
Date/Time:       05-28-01 10:10
Message Link:    http://www.8052.com/forum/read.phtml?id=11997


For all modern line transformers, the description in the  e-mail  from Gill
  Simon is not correct. There are two problems:

1) Impedance problems. Without knowing the proper termination circuits you
  will have tons of (illegal) echo on the line.

2) Modern modem transformers are not designed to handle the DC current and
  will burn. For these transformers you need to add a DC current holding
  circuit. and put a capacitor in series with the transformer to block the DC.

3) If you want to follow the description make sure you use an OLD (2400
  bps/9600 fax type) transformer or even better salvage one from an old PABX.

Jesper




---------------------------------------------------------
Message Subject: RE: 8051 C Compiler Design
Posted By:       cemil (mailto:)
Date/Time:       05-28-01 13:59
Message Link:    http://www.8052.com/forum/read.phtml?id=11998

8052 Tutorial?



---------------------------------------------------------
Message Subject: RE: How to connect PC to 4 RS232 port?
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-28-01 18:49
Message Link:    http://www.8052.com/forum/read.phtml?id=12000

If your PC has USB, get either:
<b>a).</b> a multi-port USB/Serial adaptor;
<b>b).</b> multiple single-port USB/Serial adaptors.

You might also need a hub for Option <b>(b)</b>, but it could still work out
  cheaper.

You can also get multi-port Ethernet Terminal Servers, which would allow
  multiple serial ports to connect <i>via</i> your network.


---------------------------------------------------------
Message Subject: RE: AT89S8252 flash problem
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-28-01 01:58
Message Link:    http://www.8052.com/forum/read.phtml?id=11987

I have been using the same micro: AT89S8252. Sometimes (not very often) it
  destroys data in eeprom memory. Sometimes 1, sometimes 3 bytes - I don't
  know the rule. ATMEL has published an errata for AT89S/LS8252 at its web
  site. About two weeks ago I sent it to local ATMEL's office and they didn't
  answer me yet. ATMEL is writing about revision "T" of micro, but how
  recognize this? My application is good, I think. I have been using voltage
  supervisory (TL7705), output/input drivers etc. It does not matter what is
  your applicatin in this case. ATMEL make mistake during manufacturing the
  micro, I think. You should contact the local ATMEL's office/distributor. I
  have never heard about these problems with another ATMEL's micro. Maybe you
  should to change it? If it is medical equipment, maybe using an external
  eeprom to store data is better solution?


---------------------------------------------------------
Message Subject: RE: AT89S8252 flash problem
Posted By:       Alfredo del Rio (mailto:ario@...)
Date/Time:       05-28-01 07:42
Message Link:    http://www.8052.com/forum/read.phtml?id=11996

I understand the loss of information is in the program (flash) memory, not in
  the data (E2PROM) memory. Is this true?.

I have used the AT89S53 (similar to an ATS8252 but without data -E2PROM-
  memory) and I have experienced problems in only one application. In that
  application some of the P1 port lines of the SPI were connected as inputs.
  If this is the case, care must be taken not to enter accidentally in the
  serial downloading mode, while in the power-up sequence. In my application
  the problem was solved changing some assignations of input-output lines. The
  Atmel's handbook explains -briefly- this problem.




---------------------------------------------------------
Message Subject: RE: pic to 8051 !!
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-28-01 03:43
Message Link:    http://www.8052.com/forum/read.phtml?id=11990

What "code" do you want to convert:
object?
assembler source?
'C' source?
none of the above??


---------------------------------------------------------
Message Subject: Delay code??
Posted By:       Luca Pacioli (mailto:lucapacioli@...)
Date/Time:       05-28-01 03:44
Message Link:    http://www.8052.com/forum/read.phtml?id=11991

In which way can I calculate delay in this type of code

for example:


delay:  mov R0,#255
	 mov  R1,#20
y:   djnz  R0,y
	 djnz R1,y
ret


Thanks





---------------------------------------------------------
Message Subject: RE: Delay code??
Posted By:       Alfredo del Rio (mailto:ario@...)
Date/Time:       05-28-01 05:00
Message Link:    http://www.8052.com/forum/read.phtml?id=11994

You need a table of execution times. Once you know how much time it takes to
  execute each instruction in your program, you only have to add them. Take
  into account the number of times they are repeated because of the loops.

If you prefer a faster alternative, simply simulate the program. There are
  many simulators available, some of them free. Simulators give you the
  elapsed time. Set a breakpoint at the end of your code and start the
  execution at the beginning. The delay is the elapsed time.

But remember, in many applications SW delays are not the best option!.



---------------------------------------------------------
Message Subject: RE: Delay code??
Posted By:       Gerry Keely (mailto:gery.keely@...)
Date/Time:       05-28-01 06:52
Message Link:    http://www.8052.com/forum/read.phtml?id=11995

Go to http:/www.myke.com and look under 8051 snippets


---------------------------------------------------------
Message Subject: RE: Delay code??
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-28-01 17:26
Message Link:    http://www.8052.com/forum/read.phtml?id=11999

Hi Luca,

I have only a solution for the reverse task:
calculate the register values to waste a defined amount of cycles:

http://www.specs.de/~danni/appl/soft/delay/index.htm

look at mdelay.mac

Peter



---------------------------------------------------------
Message Subject: ET-3400 trainer info...
Posted By:       Dave Kaleta (mailto:dkaleta@...)
Date/Time:       05-28-01 18:54
Message Link:    http://www.8052.com/forum/read.phtml?id=12001

Hi All,

I recently aquired the Heath Kit ET-3400 MC6800 trainer.  It had some
  electronic problem I was able to troubleshoot.  It now shows &quot;CPU
  UP.&quot;.  Unfortunately I have no books for this thing.  What I would like
  to know is the addresses for the subroutines and the I/O mapping scheme.
  Any help would be great!

Thanks,

Dave Kaleta


-------------------------------------------------------

--
Fausto Marzoli
8052 group Moderator

PER CORTESIA TOGLIMI DALLA LISTA
AVEVO SOLO BISOGNO DI UN SITO DOVE ERA ACCESSIBILE UN GRUPPO D DISCUSSIONE
SU 8051 E DERIVATI
NON SONO INTERESSATO ALLA RICEZIONE CONTINUA DI E-MAIL
GRAZIE
----- Original Message -----
From: "Fau Marz" <faumarz@...>
To: "8052 Mailing List" <8052@yahoogroups.com>
Sent: Monday, May 21, 2001 8:42 AM
Subject: [8052] Fwd: 8052.COM Mailing List - May 21st, 2001


> Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
> tratta problematiche relative alla progettazione MCS-51.
>
> In questi messaggi si possono trovare spunti interessanti.
>
>
> Saluti,
>
> --
> Fausto Marzoli
> 8052 group Moderator
>
>
> ---------------------------------------------------------
> Message Subject: Complications  in  reading  39  barcodes
> Posted By:       Arup   Chakraborty (mailto:c_arup1@...)
> Date/Time:       05-20-01 06:34
> Message Link:    http://www.8052.com/forum/read.phtml?id=11740
>
> I am currently involved in developing
> a 8052-based scanner for scanning and decoding 39 barcodes.I would like to
>  know how to get cover the complication caused by change in velocity and
>  angle of scanning wand and those by specks and voids of the ink
>
>
> ---------------------------------------------------------
> Message Subject: RE: 8052 - programmer
> Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
> Date/Time:       05-20-01 23:38
> Message Link:    http://www.8052.com/forum/read.phtml?id=11753
>
> the 8052 microcontroller I have built can be programmed over and over
angain
>  in either basic or hex. So I am not really sure what the problem is. I
will
>  be glad to help if I can.
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: components
> Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
> Date/Time:       05-20-01 23:34
> Message Link:    http://www.8052.com/forum/read.phtml?id=11752
>
> How can one design such a system without having a basic knowledge of the
>  components used? was it built from kit? anyway try a modelling program.
>  build the circuit again on it then use the component help and virtual
>  insturements to actually figure out what,s going on in the system...e.g
>  logic analyzer,probes etc
>
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: An 8052 is an 8052..... or?
> Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
> Date/Time:       05-20-01 23:53
> Message Link:    http://www.8052.com/forum/read.phtml?id=11756
>
> A golfer doesn' only use one club. Different chips for different needs....
>
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: 8052.com website organization
> Posted By:       Donatas (mailto:eziukas@...)
> Date/Time:       05-20-01 14:36
> Message Link:    http://www.8052.com/forum/read.phtml?id=11744
>
> I agree with Kathy Quinlan. It would be very good, to have possibility to
>  upload usefull files. For instance, I am beginer with 8051. I have found
a
>  lot of usefull information on this site, but not every thing. Now, I have
a
>  lot of documents in my PC, from other sites. I could upload them for
other
>  beginers. May be some of documents appear not interesting for gurus, but
>  they are necessary for those, who starts.
>
>
> ---------------------------------------------------------
> Message Subject: RE: 8052.com website organization
> Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
> Date/Time:       05-20-01 15:20
> Message Link:    http://www.8052.com/forum/read.phtml?id=11746
>
> Could you make the posibility to read all answers at the same time? Now,
we
>  have a list of answers and reading is possible, when you click one. The
>  button "SHOW ALL ANSWERS" will be very usefull, I think. Greetings.
>
>
> ---------------------------------------------------------
> Message Subject: RE: LCD display working on 24Mhz
> Posted By:       aad sieraad (mailto:aad.sieraad@...)
> Date/Time:       05-20-01 15:37
> Message Link:    http://www.8052.com/forum/read.phtml?id=11747
>
> I have it working now...
> My board runs with a 80C31 on 11.0592MHz
> and as I said: I have two 74HC573's connected to the databus and mapped in
>  memory space. With appropriate delay's it should be possible to have it
>  working at 24MHz as well because the 573's behave just like a port
really.
>  When writing to them and leaving the status as it is, it is possible to
>  create all timing needed.
>
> aad sieraad
>
>
> ---------------------------------------------------------
> Message Subject: RE: starting 89c51
> Posted By:       Kathy Quinlan (mailto:katinka@...)
> Date/Time:       05-20-01 00:43
> Message Link:    http://www.8052.com/forum/read.phtml?id=11738
>
> Ok you are doing the right things, changing EA from low to high, my
question
>  is what size is the original eprom ???
>
> The 89C51 only has 4Kbytes of eeprom so if the old eprom on the 8031 was
>  bigger than a 2732 which is 32Kbits organised in an 8 x 4 fashion (ie
>  4Kbytes)then the program above 4K is missing.
>
> Regards,
>
> Kat.
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: starting 89c51
> Posted By:       V.DURGAI DASS (mailto:durgaidass@...)
> Date/Time:       05-20-01 21:49
> Message Link:    http://www.8052.com/forum/read.phtml?id=11750
>
> Hi
>  I connected EA pin 31 (40 Pin dip) to +5V VCC. It is not working. My
>  original Eprom was 2732 and the code occupies up to 0C00 hex only. Any
other
>  cluue please.
>
> D.Dass
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: doubt about I/O of 8051
> Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
> Date/Time:       05-20-01 23:42
> Message Link:    http://www.8052.com/forum/read.phtml?id=11754
>
> that's basically it, the pin is not pulled down waiting for a 5v signal.
it's
>  pulled high waiting for a ground.
>
> Try using an inverter or a pull down resistor if thats what you like...
> hope that helps..
>
>
>
> ---------------------------------------------------------
> Message Subject: 89C51 based SCR firing
> Posted By:       Hemanth (mailto:khemanthk@...)
> Date/Time:       05-20-01 02:43
> Message Link:    http://www.8052.com/forum/read.phtml?id=11739
>
> Hello everyone,
>
>  I want a circuit which can fire SCRs used to control AC(single phase).The
>  firing angle must be controlled by a DAC interfaced with 89C51(I can
manage
>  the circuit upto DAC) This application is used for temperature control.
> The heater is 750KW.
>
> Thanks,
>
> Hemanth
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: 89C51 based SCR firing
> Posted By:       Steve M. Taylor (mailto:steve@...)
> Date/Time:       05-20-01 13:18
> Message Link:    http://www.8052.com/forum/read.phtml?id=11742
>
> Philips do a dedicated phase fire controller 8052, so you don't need to
use a
>  DAC and a lot of programming (and reliability issues) can eliminated
>
> Try using site search to find it. I think Erik Malund discovered the
device.
>
> Steve
>
>
> ---------------------------------------------------------
> Message Subject: Tx pin of 87c51/89c51
> Posted By:       Shankara Rao (mailto:shankroo@...)
> Date/Time:       05-20-01 12:07
> Message Link:    http://www.8052.com/forum/read.phtml?id=11741
>
> I am using the Tx pin as a general purpose input.The pin is connected to
the
>  out put pin of a CD 40106.We have made about 200 systems like this.We
have
>  started getting units back with 87c51 /89c51 failed with tx pin
permanently
>  high.
>
> is the failure due to the fact that the power on reset writes a 1 into the
>  pin and if the 40106 is ouputting 0 then a very heavy current flows into
the
>  port pin.
>
> There are other pins used similarly but they do not fail.
>
> Note that this a desgin upgrade from 80c31 and we had no such problem in
>  80c31.
>
> regards
>
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: Tx pin of 87c51/89c51
> Posted By:       Steve M. Taylor (mailto:steve@...)
> Date/Time:       05-20-01 13:23
> Message Link:    http://www.8052.com/forum/read.phtml?id=11743
>
> What supply are you running the 40106 from ?
>
> Steve
>
>
> ---------------------------------------------------------
> Message Subject: RE: Tx pin of 87c51/89c51
> Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
> Date/Time:       05-20-01 15:14
> Message Link:    http://www.8052.com/forum/read.phtml?id=11745
>
> I don't what causes the problem. But if you are sure, that it is too high
>  current during reset, use the diode and pull up resistor. Diode prevents
>  your circuit during POR. VCC
>
>                      | | f.e.10k
>                      |
>                      |_|
>
>               C     A |
>   TX(P3.1) _____|/|___o_____ 40106
>
>                 |\|
>
> Sorry for my "graphics", good luck.
>
>
> ---------------------------------------------------------
> Message Subject: R:Jacek
> Posted By:       aad sieraad (mailto:aad.sieraad@...)
> Date/Time:       05-20-01 15:49
> Message Link:    http://www.8052.com/forum/read.phtml?id=11748
>
> Though I appreciate your attempt I must say your circuit won't work.
> When connecting a pull-up and a diode the way you suggest it will only
cause
>  the diode to let through a 1 from the 40106 and it will prevent a 0 from
>  pulling down the input (P3.1) so this pin will always be high. It would
be
>  better to put a series resistor between the 40106 and P3.1, but I agree
with
>  Steve, I suspect a different power supply from the 40106. For connecting
a
>  UC to the outside world I mostly use a ULN2803 or 2804. These devices
have
>  open collector outputs and do not generate any voltage except the one
from
>  the pull-up.
>
>
> ---------------------------------------------------------
> Message Subject: RE: Tx pin of 87c51/89c51
> Posted By:       Shankara Rao B.s (mailto:shankroo@...)
> Date/Time:       05-20-01 23:09
> Message Link:    http://www.8052.com/forum/read.phtml?id=11751
>
> The 40106 is run from the same 5v source as the microcontroller
>
>
>
> ---------------------------------------------------------
> Message Subject: ADC0808
> Posted By:       Anil-Kashyap (mailto:anilsangani@...)
> Date/Time:       05-20-01 20:38
> Message Link:    http://www.8052.com/forum/read.phtml?id=11749
>
> Dear all,
>          we want to use an a to d converter with 89c51rd+ microcontroller
and
>  connect 0 to 5 volts variable voltage as analog input using a preset and
get
>  different addresses to the microcontroller. what is the clock frequency
that
>  we should feed to the adc0808? and how to generate it?
> we are using 12mhz crystal with microcontroller.
>         Our eariler problem of counting external events is solved. we had
to
>  use only debouncing software and no hardware changes were made. thanx for
>  all your support.
>
>
>
> ---------------------------------------------------------
> Message Subject: RE: ADC0808
> Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
> Date/Time:       05-20-01 23:46
> Message Link:    http://www.8052.com/forum/read.phtml?id=11755
>
> I use an adc0808, the processor is running at 11.97....I believe I used an
>  external 1 mhz crystal....this was an old design, so I will have to look
it
>  up for you....I am pretty sure though.
>
>
>
>
>
>
> ---------------------------------------------------------
> Message Subject: 8052 and SERVOS!
> Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
> Date/Time:       05-20-01 23:59
> Message Link:    http://www.8052.com/forum/read.phtml?id=11757
>
> hey guy's I have the 8052 controlling 5 servos with 1 serial tx line and 1
8
>  pin external chip! and 25 servos using 6 -8 pin external IC's. I can also
>  add more serial tx. I am going to try my hand at animatronics..... has
>  anyone else tried such a project?
>
>
> -------------------------------------------------------
>
> --
> Fausto Marzoli
> 8052 group Moderator
>
> --
> Per cancellare l'iscrizione a questa Mailing List, manda un messaggio
all'indirizzo:
> To unsubscribe from this group, send an email to:
> 8052-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.

Alcuni thread degni di nota oggi:

- Dual UART ?
- Flash memory and 8051


Saluti,

--
Fausto Marzoli
8052 group Moderator



---------------------------------------------------------
Message Subject: RE: Is it to interface Graphic LCD with 8051
Posted By:       maryam haider (mailto:maryam_haider@...)
Date/Time:       05-21-01 11:08
Message Link:    http://www.8052.com/forum/read.phtml?id=11782

well i have worked with 7segement displays have interfaced them with 8951
  micrcontroller i havent ever used lcd's if i can be of help
mail me at my personal e mail address
maryam


---------------------------------------------------------
Message Subject: RE: 8051 projects
Posted By:       maryam haider (mailto:maryam_haider@...)
Date/Time:       05-21-01 11:42
Message Link:    http://www.8052.com/forum/read.phtml?id=11788

im working on the 8032 microcontroller
designing a control card for a puma type robot
has anyone worked on any simial project?
i need some help



---------------------------------------------------------
Message Subject: RE:  4 digit led multiplexed display
Posted By:       maryam haider (mailto:maryam_haider@...)
Date/Time:       05-21-01 11:03
Message Link:    http://www.8052.com/forum/read.phtml?id=11780

dunno how old this msg is but i just came across it
as a matter of fact i have just finished a project similar to urs a bit more
  complex then this yes i think i can help u
send me the details
i can even provde u with a circuit diagram
and also im recomending a simulator
its at a site
ull have to download it
the url is labcenter.co.uk
go to the download section and under it shareware
there ull find the unregistered version of proteous pro demo
the size is about 10m
download it it also has a sample design of a led display interfaced with a
  micrcontroller..with an 8951 and i myself used a smilar design using a
  demux...if u think u want my design just mail ill send u a circuit diagram
its pretty easy
maryam


---------------------------------------------------------
Message Subject: RE: which development tool to buy???
Posted By:       tushar mehta (mailto:techman@...)
Date/Time:       05-21-01 10:16
Message Link:    http://www.8052.com/forum/read.phtml?id=11776

if you really wants a developement tool of 89c51. then pl. contact me on
  8089887.

or else come to my factory on saturday i will very glad to give you my
  developement tool to work.

ok, bye.


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Fausto Marzoli (mailto:faumarz@...)
Date/Time:       05-21-01 04:42
Message Link:    http://www.8052.com/forum/read.phtml?id=11764

> 1. How do you feel about the current website design?
> Is it easy-to-use?  Awkward?  Too graphical?  Not graphical enough?

It's good. A bit "confusing" the first times, maybe. Too much options.

Sometimes it takes a bit too much time to download, maybe in "high-traffic"
  moments.

> 2. Is the left sidebar useful and easy to use?
> Could the site navigation be improved or made easier to use?  If so, how?

It's easy and useful. It could be improved with something like pop-up
  submenus, I think. But I don't think it's strictly necessary.

For example, I like very much the way it's organized Philips web site, with
  popup menus for sub-browsing directly from the homepage. I know it's not
  easy to implement, but it's cool.

> 3. Would it be a good idea to eliminate the left sidebar and replace it
> with a navigation bar at the top of each page?

No. I think it's better to add a navigation bar at the top of each page, if
  you think it's useful, keeping also the left sidebar. "Repetita iuvant".
  It's better to have more than one way to browse.

One think that I would like is the possibility to post and receive the
  messages using an e-mail client instead to be online. The online forum is
  good, but for those like me that have a dial-up connection it's difficult to
  post and keep track of messages...
if I could post off-line like in a conventional mailing list it would be
  easier, I think. Now I can receive the e-mail "daily list" of messages, but
  I can't reply without being online

If there is yet this possibility, please tell me :-)


Regards,

Fausto



---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Craig Steiner (mailto:csteiner@...)
Date/Time:       05-21-01 07:54
Message Link:    http://www.8052.com/forum/read.phtml?id=11773

First, I appreciate everyone's time in responding to my question about
  improving the site. I'll be referring back to this thread on numerous
  occasions over the next couple of months since some very good ideas were
  mentioned.

Even though everyone seems to be opposed to any major change in the site's
  design, I went ahead and prepared a single page that more or less shows what
  I had in mind.

Please visit the page <A
  HREF="http://www.8052.com/alter.phtml">http://www.8052.com/alter.phtml</A>
  to see a sample of what I had in mind for a new site design.  Please check
  it out and let me know what you think here in this thread.  Also, there is a
  survey on the above page that asks you for your vote concerning the new site
  format.  I'd appreciate it if you'd participate in that survey as well.

Thanks,
Craig Steiner



---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       sanjeev kumar (mailto:sanjeevkumar_abc@...)
Date/Time:       05-21-01 10:24
Message Link:    http://www.8052.com/forum/read.phtml?id=11777

Hi all,
Great Craig But what about our forum page design ???


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Craig Steiner (mailto:csteiner@...)
Date/Time:       05-21-01 13:17
Message Link:    http://www.8052.com/forum/read.phtml?id=11790

Changes to the forum will be coming, but I want to establish the site
  organization first.  So once it is decided whether we stick with the current
  format or go to the new one then I'll work on some of the changes that need
  to be made to the forum--including an HTML preview...

Thanks,
Craig Steiner



---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Donatas (mailto:eziukas@...)
Date/Time:       05-21-01 18:44
Message Link:    http://www.8052.com/forum/read.phtml?id=11802

New design is cool. But, it would be better to use vertical, not horizontal
  bar :) If I was you, I would change black background of bar to other color.




---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-21-01 18:46
Message Link:    http://www.8052.com/forum/read.phtml?id=11803

HTML preview? <b>G-R-R-R-E-E-A-A-A-A-T-T!!!!!!!!</b>

Also, it would be useful if the answers werer fully "threaded," instead of
  all being just listed as replies to the original post


---------------------------------------------------------
Message Subject: use ASCII
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-21-01 00:18
Message Link:    http://www.8052.com/forum/read.phtml?id=11758

Use the ascii tables........


---------------------------------------------------------
Message Subject: RE: Still looking for lots of math routines.
Posted By:       Erik Malund (mailto:malund@...)
Date/Time:       05-21-01 11:42
Message Link:    http://www.8052.com/forum/read.phtml?id=11789

snippets.org

Have fun

Erik


---------------------------------------------------------
Message Subject: RE: starting 89c51
Posted By:       maryam haider (mailto:maryam_haider@...)
Date/Time:       05-21-01 11:15
Message Link:    http://www.8052.com/forum/read.phtml?id=11784

well for an 8051/8951 u need a 12mhz crystal
try that for starters



---------------------------------------------------------
Message Subject: RE: starting 89c51
Posted By:       Erik Malund (mailto:malund@...)
Date/Time:       05-21-01 11:40
Message Link:    http://www.8052.com/forum/read.phtml?id=11787

   You can run the current (static) '51s with any crystal you want, maryams
  info is at least 5 years old.  Btw 12 Mhz will lead to very poor serial
  performance.  Try debugging your eternal eprom with your ICE, most likely
  you have an address or data wire crossed.  Oh, I just remember, what latch
  are you using for the address? Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: doubt about I/O of 8051
Posted By:       Erik Malund (mailto:malund@...)
Date/Time:       05-21-01 16:40
Message Link:    http://www.8052.com/forum/read.phtml?id=11796

   download and read the 80C51_fam... documents at
  http://www-us.semiconductors.philips.com/handbook/various_66.html That will
  explain.

Have fun,

Erik


---------------------------------------------------------
Message Subject: RE: an efficient parity generation schem
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-21-01 08:29
Message Link:    http://www.8052.com/forum/read.phtml?id=11774

That's what Peter Dannegger's post did!


---------------------------------------------------------
Message Subject: RE: an efficient parity generation schem
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-21-01 10:36
Message Link:    http://www.8052.com/forum/read.phtml?id=11779

Andy,

Isn't "C" wonderfully self documenting ? A classic example of why I don't let
  C code into the building let alone into our projects.

I wonder how much code the C routine generates as a matter of interest.

Steve


---------------------------------------------------------
Message Subject: RE: an efficient parity generation schem
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-21-01 18:37
Message Link:    http://www.8052.com/forum/read.phtml?id=11801

And what exactly would you gain in assembler?  ;-)

Actually, in an example such as Peter's, the Keil C51 compiler can be
  <i>very</i> efficient: The 'bit' return value goes in the Carry flag;
The 'byte' parameter goes in a register;
ACC and P access processor objects directly


---------------------------------------------------------
Message Subject: RE: ceibo ds-51 ICE problem
Posted By:       Erik Malund (mailto:malund@...)
Date/Time:       05-21-01 11:34
Message Link:    http://www.8052.com/forum/read.phtml?id=11786

   Remember, you see the port, not the port register.  If some external device
  hlds a pin low, you can set the port high till the cows come home and it
  will stay low.

Have fun,
Erik


---------------------------------------------------------
Message Subject: RE: 89C51 based SCR firing
Posted By:       Erik Malund (mailto:malund@...)
Date/Time:       05-21-01 11:32
Message Link:    http://www.8052.com/forum/read.phtml?id=11785

   It's even on the current Philips home page, but here it is
  http://www-us.semiconductors.philips.com/industrial/infocus/

Have fun, and keep one hand in your pocket.

Erik



---------------------------------------------------------
Message Subject: RE: 89C51 based SCR firing
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-21-01 13:53
Message Link:    http://www.8052.com/forum/read.phtml?id=11792



Erik Malund wrote:
-------------------------------

Have fun, and keep one hand in your pocket.

Erik

CLARIFICATION

....not BECAUSE you have one hand in your pocket

Steve


---------------------------------------------------------
Message Subject: RE: 89C51 based SCR firing
Posted By:       Erik Malund (mailto:malund@...)
Date/Time:       05-21-01 16:23
Message Link:    http://www.8052.com/forum/read.phtml?id=11795

   just safety advice when working with high voltages.

Erik


---------------------------------------------------------
Message Subject: RE: Tx pin of 87c51/89c51
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-21-01 02:13
Message Link:    http://www.8052.com/forum/read.phtml?id=11759

Hi Shankara,

1.
You tell not, which 87c51 /89c51 derivate you use.
Maybe it can help, use another derivate (Atmel, Philips, Intel, ...).

2.
This behavior was not faulty, since the state of any pin was only defined
  after 24 crystal cycles after reset was applied.

3.
Put a 100 Ohms resistor in series to the input, which should limit the strong
  current to a safe level, but not disturb the logic level.


Peter



---------------------------------------------------------
Message Subject: RE: Tx pin of 87c51/89c51
Posted By:       Javier Piedrafita (mailto:fjpiedrafita@...)
Date/Time:       05-21-01 02:14
Message Link:    http://www.8052.com/forum/read.phtml?id=11760

It might be a problem of desing, if there is a high current in the power on
  reset you should add something to limit this current. There could be several
  reasons why until now it worked. Are you using the same manufacturer for
  both, micro and 40106, in both cases, with the 80C31 and 87C51? Chips might
  be working in the limit, in one case inside the limits but out in the other
  one. Even if it is the same manufacturer, depending on the components itself
  they may have different ratings. A set of components r ceived all together
  use to have the same ratings, but could change if you buy another set later.

Javier


---------------------------------------------------------
Message Subject: RE: 8052 and SERVOS!
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-21-01 03:22
Message Link:    http://www.8052.com/forum/read.phtml?id=11762

Yes, I built a range of animatronic displays with someone a few years
  ago,they were controlled by an 80C517 cpu.

Steve


---------------------------------------------------------
Message Subject: My at89s8252 Board
Posted By:       LIETAER Benoit (mailto:)
Date/Time:       05-21-01 03:09
Message Link:    http://www.8052.com/forum/read.phtml?id=11761

Hi everybody,

I just created my own at89s8252 board and it seems to work properly but...

1./ programming my board is very quick (not a second!) is it ok doc?

2./ once programmed, i just can't see the LEDs blinking, actually they stay
  on...For example if i want to blink P2.1 it will only turn P2.1 on but no
  squarred signal...(only dc? or is it blinking so fast i just can't see?)

3./ i need to reset my board 3 or 4 times (without the LPT1 plug) before
  getting into the software i just programmed and see my p2.1 on...otherwise i
  got some funny result on the leds (1111111,00000000, 11110011,...) I think
  the program is still in flash but hard to start..

4./What about the ISP lock bytes (bits?), how and why programming them?

Are those trouble normal?

I am mainly suspecting my 11.0 MHz (and two 27pF capa) quartz not to work
  properly or the clock signal to be bad ...can i probe it with a scope? (i
  wouldn' t do that!) Or is it my reset button that doesn't make a good reset
  signal?
can my at89s8252 be dead or the fact that it responds to your ispdos means
  that it is ok?

Do you suggest some small test? little tricks?

Thank you
Ben



---------------------------------------------------------
Message Subject: RE: My at89s8252 Board
Posted By:       Markus Siwek (mailto:markus44892@...)
Date/Time:       05-21-01 05:56
Message Link:    http://www.8052.com/forum/read.phtml?id=11769

sorry, here is the message i would send:

-&gt;1. Small progs are very fast written to the flash. The short time could
  be ok.

-&gt;2. if you have no delays in your programm, the led blink very fast. you
  don't see it.

-&gt;3. what programming tool do you use? before you program the at89s8252
  erase the flash and verify the stored data.

-&gt;4. the bits are set by the programmer. you can find the description of
  these bits in the datasheet (www.atmel.com).




---------------------------------------------------------
Message Subject: RE: My at89s8252 Board
Posted By:       LIETAER Benoit (mailto:)
Date/Time:       05-21-01 09:22
Message Link:    http://www.8052.com/forum/read.phtml?id=11775

2./I think there are delays : here is the program,

TempoL    Equ   0
TempoH    Equ   1

           ORG  0000h

Start:    Clr  A
Leds:     Mov  P2,A
           Mov  B,#0
           Mov  TempoL,#0
           Mov  TempoH,#1
Time:     Djnz B,Time
           Djnz TempoL,Time
           Djnz TempoH,Time
           CPL  A
           Jmp  Leds
end

3./i m using IspDos (from Wagner's site) and it &quot;seems&quot; to work
  fine... how can i be sure?




---------------------------------------------------------
Message Subject: Dual UART ?
Posted By:       Sascha Pypke (mailto:saschaspeedy@...)
Date/Time:       05-21-01 03:56
Message Link:    http://www.8052.com/forum/read.phtml?id=11763

Does anybody know a (low cost) Chip with two UARTs ?
ROM 1K or better RAM 128 bytes or better.
thanks,
Sascha


---------------------------------------------------------
Message Subject: RE: Dual UART ?
Posted By:       Fausto Marzoli (mailto:faumarz@...)
Date/Time:       05-21-01 04:44
Message Link:    http://www.8052.com/forum/read.phtml?id=11765

The only 8052 chip with dual UART that I know is the Dallas DS8x320/520.

If someone knows other chips, I'm interested in them too.

regards,

Fausto



---------------------------------------------------------
Message Subject: RE: Dual UART ?
Posted By:       Tommy (mailto:dragon4mil@...)
Date/Time:       05-21-01 05:00
Message Link:    http://www.8052.com/forum/read.phtml?id=11766

Hello,

Why dont you using 89c2051 with one build-in UART, and implement the second
  one in sofware (using one timer and one Ex Int)

Regards,
Tommy.




---------------------------------------------------------
Message Subject: RE: Dual UART ?
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-21-01 05:00
Message Link:    http://www.8052.com/forum/read.phtml?id=11767

Hi Sascha,

why not software UART ?


Peter



---------------------------------------------------------
Message Subject: RE: Dual UART ?
Posted By:       Sascha Pypke (mailto:saschaspeedy@...)
Date/Time:       05-21-01 07:35
Message Link:    http://www.8052.com/forum/read.phtml?id=11771

Software UART are not possible because the CPU work with an routine that need
  99% speed and timing.


---------------------------------------------------------
Message Subject: RE: Dual UART ?
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-21-01 10:31
Message Link:    http://www.8052.com/forum/read.phtml?id=11778

In that case you need a faster CPU anway !! Which one were you using ?

Steve


---------------------------------------------------------
Message Subject: RE: Dual UART ?
Posted By:       Dennis Welbourn (mailto:welbournd@...)
Date/Time:       05-21-01 11:05
Message Link:    http://www.8052.com/forum/read.phtml?id=11781

Hi Sascha,

Besides the Dallas parts, we've looked at the Winbond W77C32 and the Atmel
  TS80C51U2/TS83C51U2/TS87C51U2.  The Winbond part is romless, 1K internal
  xdata ram.  They probably also have a rom part.  The Atmel parts are 16K
  rom, OTP and eprom, but no extra ram.  The Winbond part is about half the
  price of the comparable Dallas part, and they probably have a rom version
  available.

Good luck,

Dennis


---------------------------------------------------------
Message Subject: question for LCD game
Posted By:       park kitae (mailto:shivanscimitarz@...)
Date/Time:       05-21-01 06:50
Message Link:    http://www.8052.com/forum/read.phtml?id=11770

hi, i would make game for my 8051 project.

i thought about pocket ball game.

but as start with algirithm, trouble happens...

as i know there are only shift left, or shift right instructions for lcd.

but i need lean shift(ex&gt; shift toward north-east)

how could it is possible...?

Or there are any way, not using the lcd instruction?

i will wait for your kind reply.

thank you


---------------------------------------------------------
Message Subject: RE: question for LCD game
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-21-01 07:50
Message Link:    http://www.8052.com/forum/read.phtml?id=11772

Which LCD ? What are the &quot;rules&quot; of your game ?

Steve


---------------------------------------------------------
Message Subject: RE: question for LCD game
Posted By:       park kitae (mailto:shivanscimitarz@...)
Date/Time:       05-21-01 11:08
Message Link:    http://www.8052.com/forum/read.phtml?id=11783

thank you for your reply.

i will make pocket ball game.

if is push the button, on LCD, the ball rolls across display.

when it faces the wall, it will reflect at the same angle with its incoming
  angle(or incident angle).

well....maybe it will not be a sufficient illustration....

but the point is the shifting with angle....

how could it be implemented for the case of 5 line LCD?

PS&gt; another question....

for 2 line LCD, second line address starts from 40h.

then, for 5 line LCD, what is the start addess of third line?


---------------------------------------------------------
Message Subject: LCD driver
Posted By:       Andres (mailto:andreso@...)
Date/Time:       05-21-01 13:44
Message Link:    http://www.8052.com/forum/read.phtml?id=11791

Hi!

  everyone

  I have something here, I'm developing a few diferent projects with the
  AT89C52 and one of them involve an LCD ...

  Well I talk to a rep. from Hitachi and they are no longer supporting the HD
  44780. is there any other manufacturer or an equivalent part number??

thanks for your help


---------------------------------------------------------
Message Subject: Flash memory and 8051
Posted By:       Vincent (mailto:vincent@...)
Date/Time:       05-21-01 15:47
Message Link:    http://www.8052.com/forum/read.phtml?id=11793

Is there somebody with experience to interface a memory flash type M28F512
  and a 80c32? Thanks in advance, and sorry for my bad english.
Vincent.


---------------------------------------------------------
Message Subject: RE: Flash memory and 8051
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-21-01 15:53
Message Link:    http://www.8052.com/forum/read.phtml?id=11794

How do you want to interface it ? it looks just like a normal eprom to the
  system

Steve


---------------------------------------------------------
Message Subject: RE: Flash memory and 8051
Posted By:       Vincent (mailto:vincent@...)
Date/Time:       05-21-01 17:26
Message Link:    http://www.8052.com/forum/read.phtml?id=11798

Thanks for you answer Steve, My target is to load the program in the flash by
  the the serial link of the 80C32 via a boot loader resident in the flash
  adress 0000H.


---------------------------------------------------------
Message Subject: RE: Flash memory and 8051
Posted By:       Vincent (mailto:vincent@...)
Date/Time:       05-21-01 17:26
Message Link:    http://www.8052.com/forum/read.phtml?id=11799

Thanks for you answer Steve, My target is to load the program in the flash by
  the the serial link of the 80C32 via a boot loader resident in the flash
  adress 0000H. Vincent.


---------------------------------------------------------
Message Subject: Comparing two numbers
Posted By:       Roger Johansson (mailto:roger@...)
Date/Time:       05-21-01 17:06
Message Link:    http://www.8052.com/forum/read.phtml?id=11797

Hello,
I'm not so good in assembler programming and I have a problem were I need to
  compare two values with each other to se if the values are the same size or
  one is larger than the other. I thought I could use subb but I don’t know
  what happens is the values are the same. Probably easy to do when you know
  how ;-)
Thanks
/Roger



---------------------------------------------------------
Message Subject: RE: Comparing two numbers
Posted By:       Andy Neil (mailto:awneil@...)
Date/Time:       05-21-01 18:22
Message Link:    http://www.8052.com/forum/read.phtml?id=11800

Get a good reference on the 8051 instruction set, <i>eg,</i> the Philips
  <i>80C51 Family Programmer's Guide and Instruction Set</i>
  http://www.semiconductors.philips.com/acrobat/various/80C51_FAM_PROG_GUIDE_1
.pdf

Look at all the conditional jump instructions - you'll probably need to do
  some sort of subtraction, then test the appropriate flag for the condition
  you want (greater/equal/less/etc).





---------------------------------------------------------
Message Subject: RE: Comparing two numbers
Posted By:       Craig Steiner (mailto:csteiner@...)
Date/Time:       05-21-01 22:11
Message Link:    http://www.8052.com/forum/read.phtml?id=11805

Check out the <A HREF="http://www.8052.com/51cjne.phtml">CJNE</A>
  instruction.  The instruction is CJNE operand1,operand2,BranchAddress

"The Carry bit (C) is set if operand1 is less than operand2, otherwise it is
  cleared."

So a common structure is:

CJNE A,address,$+3
JC A_smaller_than_address
SJMP A_greater_or_equal_to_address

Additionally, CJNE doesn't change accumulator nor the contents of
  <I>address</I> while SUBB will change the accumulator.

Good luck,
Craig Steiner



---------------------------------------------------------
Message Subject: Remote control with HT-12E/D
Posted By:       Damian Ariel Albano (mailto:damianalbano@...)
Date/Time:       05-21-01 20:23
Message Link:    http://www.8052.com/forum/read.phtml?id=11804

Hi:
    I'm working on a project where I have to control remotely three servos.
  I'm planing to use HT-12 E and HT-12 D but I'm not sure about how do they
  work. How often should I change the imput data on the encoder HT-12 E??? I'm
  planning to transmit 12 bits of data for every change on the position of the
  servos.

Thank you in advance for your help


-------------------------------------------------------

--
Fausto Marzoli
8052 group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.


Saluti,

--
Fausto Marzoli
8052 group Moderator


---------------------------------------------------------
Message Subject: Complications  in  reading  39  barcodes
Posted By:       Arup   Chakraborty (mailto:c_arup1@...)
Date/Time:       05-20-01 06:34
Message Link:    http://www.8052.com/forum/read.phtml?id=11740

I am currently involved in developing
a 8052-based scanner for scanning and decoding 39 barcodes.I would like to
  know how to get cover the complication caused by change in velocity and
  angle of scanning wand and those by specks and voids of the ink


---------------------------------------------------------
Message Subject: RE: 8052 - programmer
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-20-01 23:38
Message Link:    http://www.8052.com/forum/read.phtml?id=11753

the 8052 microcontroller I have built can be programmed over and over angain
  in either basic or hex. So I am not really sure what the problem is. I will
  be glad to help if I can.



---------------------------------------------------------
Message Subject: RE: components
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-20-01 23:34
Message Link:    http://www.8052.com/forum/read.phtml?id=11752

How can one design such a system without having a basic knowledge of the
  components used? was it built from kit? anyway try a modelling program.
  build the circuit again on it then use the component help and virtual
  insturements to actually figure out what,s going on in the system...e.g
  logic analyzer,probes etc




---------------------------------------------------------
Message Subject: RE: An 8052 is an 8052..... or?
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-20-01 23:53
Message Link:    http://www.8052.com/forum/read.phtml?id=11756

A golfer doesn' only use one club. Different chips for different needs....




---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Donatas (mailto:eziukas@...)
Date/Time:       05-20-01 14:36
Message Link:    http://www.8052.com/forum/read.phtml?id=11744

I agree with Kathy Quinlan. It would be very good, to have possibility to
  upload usefull files. For instance, I am beginer with 8051. I have found a
  lot of usefull information on this site, but not every thing. Now, I have a
  lot of documents in my PC, from other sites. I could upload them for other
  beginers. May be some of documents appear not interesting for gurus, but
  they are necessary for those, who starts.


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-20-01 15:20
Message Link:    http://www.8052.com/forum/read.phtml?id=11746

Could you make the posibility to read all answers at the same time? Now, we
  have a list of answers and reading is possible, when you click one. The
  button "SHOW ALL ANSWERS" will be very usefull, I think. Greetings.


---------------------------------------------------------
Message Subject: RE: LCD display working on 24Mhz
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-20-01 15:37
Message Link:    http://www.8052.com/forum/read.phtml?id=11747

I have it working now...
My board runs with a 80C31 on 11.0592MHz
and as I said: I have two 74HC573's connected to the databus and mapped in
  memory space. With appropriate delay's it should be possible to have it
  working at 24MHz as well because the 573's behave just like a port really.
  When writing to them and leaving the status as it is, it is possible to
  create all timing needed.

aad sieraad


---------------------------------------------------------
Message Subject: RE: starting 89c51
Posted By:       Kathy Quinlan (mailto:katinka@...)
Date/Time:       05-20-01 00:43
Message Link:    http://www.8052.com/forum/read.phtml?id=11738

Ok you are doing the right things, changing EA from low to high, my question
  is what size is the original eprom ???

The 89C51 only has 4Kbytes of eeprom so if the old eprom on the 8031 was
  bigger than a 2732 which is 32Kbits organised in an 8 x 4 fashion (ie
  4Kbytes)then the program above 4K is missing.

Regards,

Kat.



---------------------------------------------------------
Message Subject: RE: starting 89c51
Posted By:       V.DURGAI DASS (mailto:durgaidass@...)
Date/Time:       05-20-01 21:49
Message Link:    http://www.8052.com/forum/read.phtml?id=11750

Hi
  I connected EA pin 31 (40 Pin dip) to +5V VCC. It is not working. My
  original Eprom was 2732 and the code occupies up to 0C00 hex only. Any other
  cluue please.

D.Dass



---------------------------------------------------------
Message Subject: RE: doubt about I/O of 8051
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-20-01 23:42
Message Link:    http://www.8052.com/forum/read.phtml?id=11754

that's basically it, the pin is not pulled down waiting for a 5v signal. it's
  pulled high waiting for a ground.

Try using an inverter or a pull down resistor if thats what you like...
hope that helps..



---------------------------------------------------------
Message Subject: 89C51 based SCR firing
Posted By:       Hemanth (mailto:khemanthk@...)
Date/Time:       05-20-01 02:43
Message Link:    http://www.8052.com/forum/read.phtml?id=11739

Hello everyone,

  I want a circuit which can fire SCRs used to control AC(single phase).The
  firing angle must be controlled by a DAC interfaced with 89C51(I can manage
  the circuit upto DAC) This application is used for temperature control.
The heater is 750KW.

Thanks,

Hemanth



---------------------------------------------------------
Message Subject: RE: 89C51 based SCR firing
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-20-01 13:18
Message Link:    http://www.8052.com/forum/read.phtml?id=11742

Philips do a dedicated phase fire controller 8052, so you don't need to use a
  DAC and a lot of programming (and reliability issues) can eliminated

Try using site search to find it. I think Erik Malund discovered the device.

Steve


---------------------------------------------------------
Message Subject: Tx pin of 87c51/89c51
Posted By:       Shankara Rao (mailto:shankroo@...)
Date/Time:       05-20-01 12:07
Message Link:    http://www.8052.com/forum/read.phtml?id=11741

I am using the Tx pin as a general purpose input.The pin is connected to the
  out put pin of a CD 40106.We have made about 200 systems like this.We have
  started getting units back with 87c51 /89c51 failed with tx pin permanently
  high.

is the failure due to the fact that the power on reset writes a 1 into the
  pin and if the 40106 is ouputting 0 then a very heavy current flows into the
  port pin.

There are other pins used similarly but they do not fail.

Note that this a desgin upgrade from 80c31 and we had no such problem in
  80c31.

regards




---------------------------------------------------------
Message Subject: RE: Tx pin of 87c51/89c51
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-20-01 13:23
Message Link:    http://www.8052.com/forum/read.phtml?id=11743

What supply are you running the 40106 from ?

Steve


---------------------------------------------------------
Message Subject: RE: Tx pin of 87c51/89c51
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-20-01 15:14
Message Link:    http://www.8052.com/forum/read.phtml?id=11745

I don't what causes the problem. But if you are sure, that it is too high
  current during reset, use the diode and pull up resistor. Diode prevents
  your circuit during POR. VCC

                      | | f.e.10k
                      |
                      |_|

               C     A |
   TX(P3.1) _____|/|___o_____ 40106

                 |\|

Sorry for my "graphics", good luck.


---------------------------------------------------------
Message Subject: R:Jacek
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-20-01 15:49
Message Link:    http://www.8052.com/forum/read.phtml?id=11748

Though I appreciate your attempt I must say your circuit won't work.
When connecting a pull-up and a diode the way you suggest it will only cause
  the diode to let through a 1 from the 40106 and it will prevent a 0 from
  pulling down the input (P3.1) so this pin will always be high. It would be
  better to put a series resistor between the 40106 and P3.1, but I agree with
  Steve, I suspect a different power supply from the 40106. For connecting a
  UC to the outside world I mostly use a ULN2803 or 2804. These devices have
  open collector outputs and do not generate any voltage except the one from
  the pull-up.


---------------------------------------------------------
Message Subject: RE: Tx pin of 87c51/89c51
Posted By:       Shankara Rao B.s (mailto:shankroo@...)
Date/Time:       05-20-01 23:09
Message Link:    http://www.8052.com/forum/read.phtml?id=11751

The 40106 is run from the same 5v source as the microcontroller



---------------------------------------------------------
Message Subject: ADC0808
Posted By:       Anil-Kashyap (mailto:anilsangani@...)
Date/Time:       05-20-01 20:38
Message Link:    http://www.8052.com/forum/read.phtml?id=11749

Dear all,
          we want to use an a to d converter with 89c51rd+ microcontroller and
  connect 0 to 5 volts variable voltage as analog input using a preset and get
  different addresses to the microcontroller. what is the clock frequency that
  we should feed to the adc0808? and how to generate it?
we are using 12mhz crystal with microcontroller.
         Our eariler problem of counting external events is solved. we had to
  use only debouncing software and no hardware changes were made. thanx for
  all your support.



---------------------------------------------------------
Message Subject: RE: ADC0808
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-20-01 23:46
Message Link:    http://www.8052.com/forum/read.phtml?id=11755

I use an adc0808, the processor is running at 11.97....I believe I used an
  external 1 mhz crystal....this was an old design, so I will have to look it
  up for you....I am pretty sure though.






---------------------------------------------------------
Message Subject: 8052 and SERVOS!
Posted By:       Daxx Teryn (mailto:ROBSCIX@...)
Date/Time:       05-20-01 23:59
Message Link:    http://www.8052.com/forum/read.phtml?id=11757

hey guy's I have the 8052 controlling 5 servos with 1 serial tx line and 1 8
  pin external chip! and 25 servos using 6 -8 pin external IC's. I can also
  add more serial tx. I am going to try my hand at animatronics..... has
  anyone else tried such a project?


-------------------------------------------------------

--
Fausto Marzoli
8052 group Moderator

Inoltro alcuni messaggi tratti dal forum 8052.com, un forum on-line che
tratta problematiche relative alla progettazione MCS-51.

In questi messaggi si possono trovare spunti interessanti.

Alcuni thread degni di nota oggi:

- LCD display working on 24Mhz
- an efficient parity generation schem


Saluti,

--
Fausto Marzoli
8052 group Moderator

---------------------------------------------------------
Message Subject: RE: PWM
Posted By:       Paulo Miguel Magalhaes (mailto:PMSM@...)
Date/Time:       05-19-01 06:32
Message Link:    http://www.8052.com/forum/read.phtml?id=11716

I'm searching one program to create and control a PWM.
If somebody have some stuff about it, i apreciate.
Cheers,
Paulo Miguel.


---------------------------------------------------------
Message Subject: RE: A Beginner in need of help
Posted By:       Andre Bauer (mailto:Andre-Bauer@...)
Date/Time:       05-19-01 12:24
Message Link:    http://www.8052.com/forum/read.phtml?id=11724

Hello!

The programmer works fine, but before the software read or write the
  microcontroller, it does a basic check of the hardware. It try to push some
  data through the 74HC595 and the 74HC157 and read it back. When the
  programmer seems to work not correctly, the message "...please check
  power supply and connections..." appears.

When you are certain, that you have built the programmer layout correctly,
  please try the following: - Goto the software options and deselect the
  option "Check programmer before access".

Regards,

André Bauer
http://Batronix.com


---------------------------------------------------------
Message Subject: RE: Serial line with one Master
Posted By:       anurag parkash (mailto:anuragparkash@...)
Date/Time:       05-19-01 08:14
Message Link:    http://www.8052.com/forum/read.phtml?id=11717

hi alok
yes i want some project on 8051. can u send me some details
anurag


---------------------------------------------------------
Message Subject: RE: Serial line with one Master
Posted By:       Tommy (mailto:dragon4mil@...)
Date/Time:       05-19-01 08:47
Message Link:    http://www.8052.com/forum/read.phtml?id=11718

Me too.

Can anybody send me some examples or link to implement one master - multi
  slave communication ?


dragon4mil@...
Thanks.


---------------------------------------------------------
Message Subject: RE: PBM 3960 to 8051
Posted By:       Kathy Quinlan (mailto:katinka@...)
Date/Time:       05-19-01 21:14
Message Link:    http://www.8052.com/forum/read.phtml?id=11736

Ok all thanks for your help on this problem I now have it working.

Fell into a few newbie traps, jumping to a subroutine, then returing from it
  with a return instruction, or acalling it then jumping out of it.

Also made a few errors calculating the jumps in a look up table for the motor
  currents :o(

Although I have been programming on the 8051 for over 8 years now, but due to
  doing stuff all in the last year I missed afew traps and felt like a newbie
  once again, so after all these problems I am planning on doing a tutorial
  for newbies showing some of the pitfalls of writing and modifying a program,
  like stack overflow, underflow, and where the various registers and bit
  programable areas are. Although this is all explained in the pdf files from
  the various manufacturers, these are very large document and are daunting to
  the new used to sift through.


Regards,

Kat.



---------------------------------------------------------
Message Subject: RE: need help getting started
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-19-01 11:35
Message Link:    http://www.8052.com/forum/read.phtml?id=11722

Hi Aad,

the error at "org 0Bh" can have some reasons:
1. there was already code written at 0Bh

2. some simple assemblers accept no org statement with values below the
  current address.


Also I think, its not easy to start with an 8051 and already immense hardware
  attach on it. If I would start now with the 8051, I would build a board with
  nothing more than: - the AT89S8252,
- P1.5 - P1.7, Reset connected to the printer port for download,
- 10µF from Reset to VCC
- crystal 11.0592MHz + 2 * 33pF
- 8 switches against GND on P2
- 8 LEDs + 8 * 1kOhm against VCC on P0


Peter



---------------------------------------------------------
Message Subject: RE: need help getting started
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-19-01 12:14
Message Link:    http://www.8052.com/forum/read.phtml?id=11723

Thanks Peter,
But I already have the watchdog and the timer0 interrupt under control. I am
  now working on the LCD. I have 2 573's on the A/D bus and already have a
  blinking cursor. Still looking for a reason I can't write any characters
  yet. Must be a simple thing again. Haven't used the right code yet I guess.


---------------------------------------------------------
Message Subject: RE: 80c537/ 517 Port 6
Posted By:       Anders Sandström (mailto:aos@...)
Date/Time:       05-19-01 03:07
Message Link:    http://www.8052.com/forum/read.phtml?id=11711

OK, I was in a hurry when answering and did not read table 4.1 as
well as I should have. Last adress in that table is for P5 on F8, no
P6 on FA, one can find it higher up on adress DB , so P6 is on different
  adresses in 537 and 535.

Anders


---------------------------------------------------------
Message Subject: RE: Good Transceiver For serial BUS?
Posted By:       sanjeev kumar (mailto:sanjeevkumar_abc@...)
Date/Time:       05-19-01 02:04
Message Link:    http://www.8052.com/forum/read.phtml?id=11709

Erik Malund wrote:
-------------------------------
the '243 is a parrallel bus multiplexer and you talk about a "THE
  serial .

Hi Erik,
74LS243 is quad transceiver (3-states).Though it is used with the parallel
  bus but I wired experimentally with the serial bus alloting 3 drivers each
  for tx & rx side,in order disable the serial bus from the slaves to
  avoide crosstalk but the moment I give it power the '243 gets heated and
  when serial communication is allowed the situation worsen .I have now
  changed the design with the AND gates i.e two drivers each for TX  & RX
  side to share the load hope this will work .what do you suggest?

Thanks
Sanjeev


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Donatas (mailto:eziukas@...)
Date/Time:       05-19-01 12:58
Message Link:    http://www.8052.com/forum/read.phtml?id=11725

I think, one thing can by done - NO GRAPHIC at all! Use only text links
  isteed of those buttons in the left bar.You could change some colors. Now,
  it is a little bit sad atmosphera. But do not use more then 3 colors! but
  every thing is cool in this site.


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Dincer Aydin (mailto:)
Date/Time:       05-19-01 16:08
Message Link:    http://www.8052.com/forum/read.phtml?id=11730

I also think that the images on the left side bar can be eliminated. They are
  about 35Kb in total size and 20+ in number. The page would load much faster
  without them.

Regards,

Dincer Aydin


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-19-01 17:16
Message Link:    http://www.8052.com/forum/read.phtml?id=11732

35K on this PC loads in less than 2 seconds.

Steve


---------------------------------------------------------
Message Subject: RE: 8052.com website organization
Posted By:       Kathy Quinlan (mailto:katinka@...)
Date/Time:       05-19-01 20:57
Message Link:    http://www.8052.com/forum/read.phtml?id=11735

I love the site the way it is Craig, only changes I would make are :

1) make a link where we can send stuff for the tutorials and code libraray,
  maybe an area that registered users can get to so that multiple users can
  contribute to a tutorial.

2) more ads with free stuff (I am bad I know) just I tend to buy more from
  companies who send out freebies as it means if a part is not suited then I
  have not wasted any money.

Regards,


Kat.



---------------------------------------------------------
Message Subject: RE: LCD display working on 24Mhz
Posted By:       Richard King (mailto:lionheart@...)
Date/Time:       05-19-01 00:24
Message Link:    http://www.8052.com/forum/read.phtml?id=11707

Hi,

Memory mapping should work OK - it does on the Atmel STK200 (?) evaluation
  board (there's a sketch of this buried somewhere on my bench!) AND they read
  back the busy signal! If you don't want to check the busy signal, use a
  timer interrupt to copy the characters from a RAM buffer to the display - at
  least this way your program can get on with other stuff during the delay.
  Just count a few extra cycles after sending the control codes (count a few
  more for the home code, I think). Watch the signal timing! set-up times & so
  on).

Good luck,

RWK

BTW what do LED & LCD mean, then look at the subject again ;-)



---------------------------------------------------------
Message Subject: RE: LCD display working on 24Mhz
Posted By:       Leo Paul (mailto:leo_paul@...)
Date/Time:       05-19-01 03:11
Message Link:    http://www.8052.com/forum/read.phtml?id=11712

Hi,
you can connect the LCD data bus directly to the 8051's data bus. but it is a
  good practice to buffer through a  74HCT245.follow the ckt below. a 2 input
  NAND gate will do __________ /E
  /WR--|    |            |

       | /& |----|    |  | |    |

  /RD--|    |    | /& |----| /& |----E

  LCD_CS---------|    |

  /WR--------------------------------R/W

   A0--------------------------------R/S

you can use the spare NAND to invert the /LCD_CS from the address decoder.
the /LCD_CS is memory mapped. if you are using '245, control the data
  direction by using /WR or /RD






---------------------------------------------------------
Message Subject: RE: LCD display working on 24Mhz
Posted By:       Leo Paul (mailto:leo_paul@...)
Date/Time:       05-19-01 03:19
Message Link:    http://www.8052.com/forum/read.phtml?id=11713

sorry for the mess in my previous posting.

you can connect the LCD data bus directly to the 8051's data bus. but it is a
  good practice to buffer through a 74HCT245.follow the ckt below. a 2 input
  NAND gate will do

LCD  ---  8051
  E = !((/WR nand /RD ) nand ( LCD_CS ))

  R/W  = /WR

  C/D  = A0

you can use the spare NAND to invert the /LCD_CS from the address decoder.
the /LCD_CS is memory mapped. if you are using '245, control the data
  direction by using /WR or /RD



---------------------------------------------------------
Message Subject: project
Posted By:       anele nkunkuma (mailto:nichogt@...)
Date/Time:       05-19-01 14:37
Message Link:    http://www.8052.com/forum/read.phtml?id=11727

I need to know about how I can program the 8052 cip using Microvision
to drive a small car,Built from mecano set.The car must go forward and
  reverse when it  hit a opstacle .The car must delay for few minuts and
  change direction either to the right or the left side.

Please email me the answers or refer me to other web site.


---------------------------------------------------------
Message Subject: starting 89c51
Posted By:       V.DURGAI DASS (mailto:durgaidass@...)
Date/Time:       05-19-01 02:06
Message Link:    http://www.8052.com/forum/read.phtml?id=11710

Hi all,

I copied a working code for 8031 with 10Mhz cstl, in to a 89c51 and put 89c51
  inplace of 8031. The cct works well with the Eprom. Now i removed the eprom
  and connected pin31 of uc to +5V. But the cct does not work with internal
  program in 89c51. What mistake I am doing.

D.Dass


---------------------------------------------------------
Message Subject: RE: starting 89c51
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-19-01 14:46
Message Link:    http://www.8052.com/forum/read.phtml?id=11728

Are you sure, that address space for each memory is the same? I have made the
  same change as you, but my program works correct.. Maybe you make mistake
  during programing eeprom? Maybe your mistake is trying to change device
  which is working correct (sorry, it is a joke...)


---------------------------------------------------------
Message Subject: doubt about I/O of 8051
Posted By:       Alessandro Carboni (mailto:coals@...)
Date/Time:       05-19-01 06:05
Message Link:    http://www.8052.com/forum/read.phtml?id=11714

If the pin is set for input why it has 5V ??? If there are 5V in which
way the mC can read the pin???
Isn't more logic that there are 0 V???

thanks


---------------------------------------------------------
Message Subject: RE: doubt about I/O of 8051
Posted By:       aad sieraad (mailto:aad.sieraad@...)
Date/Time:       05-19-01 08:47
Message Link:    http://www.8052.com/forum/read.phtml?id=11719

Easy, when the input is 5V it means it is NOT pulled down by an external
  device i.e. switch or transistor or whatever. So the MC will return a
  logical 1 when it reads the pin. If you attach a switch from the input pin
  to gnd and toggle it you'll see the status change from 1 to 0.


---------------------------------------------------------
Message Subject: an efficient parity generation scheme ?
Posted By:       Tommy (mailto:dragon4mil@...)
Date/Time:       05-19-01 06:29
Message Link:    http://www.8052.com/forum/read.phtml?id=11715

Hello,

I'm looking for an efficient parity generation scheme in sofware (parity
  calcularted by XORing all data bits).

Anybody can help ?

Thanks.



---------------------------------------------------------
Message Subject: RE: an efficient parity generation scheme ?
Posted By:       Peter Dannegger (mailto:danni@...)
Date/Time:       05-19-01 11:12
Message Link:    http://www.8052.com/forum/read.phtml?id=11721

#pragma cd
#include<reg51.h>

bit parity(char b)
{
   ACC = b;
   return P;
}



---------------------------------------------------------
Message Subject: RE: an efficient parity generation scheme ?
Posted By:       Txip (mailto:)
Date/Time:       05-19-01 13:09
Message Link:    http://www.8052.com/forum/read.phtml?id=11726


Here's a snippet of code for PIC processors (full offtopic here, hehe).
  Credit due to its author.

Work left: translate it into 8051 code, I'm too lazy now...

Txip.

---
The six instructions below (provided by John Payson) will calculate the
  "Even" Parity for a Byte. At the end of the routine, bit 0 of
  "X" will have the "Even" Parity bit of the original
  number.

"Even" Parity means that if all the "1"s in the byte are
  summed along with Parity Bit, an even number will be produced.

   swapf  X,w
   xorwf  X,f

   rrf    X,w
   xorwf  X,f

   btfsc  X,2
    incf  X,f

---


---------------------------------------------------------
Message Subject: RE: an efficient parity generation schem
Posted By:       Steve M. Taylor (mailto:steve@...)
Date/Time:       05-19-01 17:08
Message Link:    http://www.8052.com/forum/read.phtml?id=11731

Use the PSWs parity flag ?

Steve


---------------------------------------------------------
Message Subject: RE: an efficient parity generation schem
Posted By:       Tommy (mailto:dragon4mil@...)
Date/Time:       05-19-01 18:26
Message Link:    http://www.8052.com/forum/read.phtml?id=11733

Hello Taylor,

Could you pls explain in more detail ?

Thank you.



---------------------------------------------------------
Message Subject: RE: an efficient parity generation schem
Posted By:       Tommy (mailto:dragon4mil@...)
Date/Time:       05-19-01 19:07
Message Link:    http://www.8052.com/forum/read.phtml?id=11734

Hi Taylo,

Then what I have to to is load data to the accumulator and parity is boit 0
  of PSW ?


Regards ?


---------------------------------------------------------
Message Subject: Question about timer
Posted By:       Tommy (mailto:dragon4mil@...)
Date/Time:       05-19-01 08:51
Message Link:    http://www.8052.com/forum/read.phtml?id=11720

Hello all,

I have a question.

If I use hardware build-in UART in mode 2, is it timer 1 then free for other
  purpose ?


Regards,

Tommy


---------------------------------------------------------
Message Subject: RE: Question about timer
Posted By:       Jacek Bogusz (mailto:jacek.bogusz@...)
Date/Time:       05-19-01 14:55
Message Link:    http://www.8052.com/forum/read.phtml?id=11729

Philips' "80C51 family programmer's guide and instruction set"
The baud are fixed in this mode and 1/32 or 1/64 of oscillator frequency,
  depending on the value of SMOD bit in PCON register. In this mode none of
  Timers are used and the clock comes from internal phase 2 clock.

* * * * * * * * *
So, why not?


---------------------------------------------------------
Message Subject: ceibo ds-51 ICE problem
Posted By:       Moskovitz Elieer (mailto:mos_ko@...)
Date/Time:       05-19-01 21:42
Message Link:    http://www.8052.com/forum/read.phtml?id=11737

I have ceibo ICE and I try to run a hex file in Emulation mode. running it
  line by line when I change a port and looked at it in the watch window I see
  that no mater what I do it's changing to 0 instead of to my number what
  maybe I'm doing wrong.

mosko

-------------------------------------------------------

--
Fausto Marzoli
8052 group Moderator